Minecraft Wiki:Issues/1.2.3

Organization of This Page & Instructions
Please do not spontaneously delete an issue report or comment, unless it is patent nonsense submitted by someone who has not logged in. If possible, contact the submitter by user-talk first and tell them about your concerns. They will almost certainly oblige. As always, assume good faith.

If you're unsure of an issue, it's good practice to post about it on the talk page to see whether others can reproduce it. Make sure you're testing the bug in the correct version (for this page, that's 1.2.3) with no mods installed. Also, make sure to proofread your issue report before submitting it; unintelligible issue reports come off as inconsiderate and disrespectful. Finally, please determine which game mode(s) your issue appears in, and flag it with the appropriate label(s). (Also, note that if, for example, a minor annoyance appears in both single-player and multiplayer, and in both creative and survival modes, you should label it as [A], not [A][SP][MP][Su][Cr].)

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Issue Labels
Please mark your issue with one of these issue labels: (listed from highest priority to lowest)
 * !! =  = Critical bug that can crash a Minecraft client or server.
 * ! =  = Major bug. Use this tag sparingly; if there is consensus your bug is not major, it will be downgraded.
 * a! =  = Major annoyance.  Think very carefully before flagging an annoyance as major.  Is it really more important than most minor bugs?  Use this tag sparingly; if there is consensus your annoyance is not major, it will be downgraded.
 * undefined =  = Minor bug.
 * a =  = Annoyance.
 * ? =  = Potential issue that you are unsure of or that the community (on the discussion page) believes requires further vetting.  Note: do not use this label to indicate this-is-not-a-bug; instead, replace the issue's current label with [A] or [A!].  Furthermore, it is inappropriate to use this to flag something you disagree with; instead, express your opinion in a comment. When you apply this label to an issue, place it after the issue's existing labels; do not remove those labels.

Labels for indicating that an issue happens only in a particular game mode: (These labels cannot stand alone; you must use them in addition to, not instead of, the ones listed above.)
 * sp =  = Single-player.
 * mp =  = Multiplayer.
 * su =  = Survival mode.
 * cr =  = Creative mode.

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 * =  = Mac OS X
 * =  = Windows
 * =  = GNU/Linux

Labels that Mojang (not you!) uses: (Please place these tags in front of existing issue labels; do not remove the existing labels.)
 * f = Issue for which a fix will appear in the next update.
 * n = Not a bug; intended behavior. By definition, this label is inapplicable to annoyances; annoyances are not bugs.
 * s = Issue that will not be fixed in the next update.
 * u = Issue that Mojang has tested but was unable to reproduce.

To produce these labels, use the following code:  c where c is the code of the label you wish to use. (e.g., a for annoyances, etc.)

The default issue type is minor bug; you can produce this label with the shorthand  undefined .

Crashing/System
Bugs !!mp You will have problems if you warp between worlds where start and end warp have nearby coordinates, because of new chunk network transfer optimization. Chunk data collides and client crashes. This has been experienced by many players on my server and in my case specifically, it seems to sometimes make my graphics drivers stop responding and reload, as well. For the record, even if no crash occurs, old chunks can still be seen in the distance, sometimes long after leaving a world. My personal system for reference is Win7 64-bit, Java 7 64-bit with 5Gb allocated to MC. Graphics is a Radeon 6990 and tested with both 12.1 and updated drivers, if this helps narrow the problem at all. Here is also a paste of a partial error log from a player with this issue: http://pastie.org/3527988 Snaiperskaya 18:22, 5 March 2012 (UTC)

!!mp Server crashes regularly in vanilla 1.2.3 2012-03-04 19:04:50 [SEVERE] Unexpected exception java.lang.ArrayIndexOutOfBoundsException: -8 at mw.h(SourceFile:275) at mw.a(SourceFile:390) at mw.a(SourceFile:346) at gd.b(SourceFile:392) at gd.e(SourceFile:453) at yt.a(SourceFile:77) at gd.l(SourceFile:2016) at gd.h(SourceFile:1795) at net.minecraft.server.MinecraftServer.w(SourceFile:426) at net.minecraft.server.MinecraftServer.run(SourceFile:356) at dm.run(SourceFile:490) This happens every few hours now, and whilst the server is still apparently running (I can 'stop' it), everyone gets booted and no one else can log in. I can't work out what causes the crash, but it's always in mw.h, line 275. I'm not the only person seeing this either (google for "java.lang.ArrayIndexOutOfBoundsException: -8" and you'll see a lot of threads. I'm happy to put the world somewhere public, or do whatever I can else to help.

The server is an iMac running OSX 10.7.3 btw (so it's completely up to date). --Drspindizzy 12:49, 5 March 2012 (UTC)


 * This one (java.lang.ArrayIndexOutOfBoundsException: -8) has happened to me as well, and I was able to fix it. For me, there was an area of my map which would crash the server if a player approached it.  If you are unlucky enough to have a user who logged out near that point, the server would crash a few seconds after they logged in.  After some trial and error, I narrowed it down to some chunks which contained an extremely tall structure (E.g., a building with a roof at the highest possible point in the pre-1.2 world).  I opened the world in mcedit, and lowered the roofs in question by 1 block, and now it works fine and my server has stopped crashing.  My guess is that having blocks at the top of the world might confuse the conversion process somehow.  I did note that in 1.1, the lighting of that roof was never right.  Now it looks fine and does not crash.  JohnQ


 * My friend had this issue on his remote linux box (virtual private server, Archlinux; I lack version info. though). We thought that could be caused by an outdated Java Runtime Environment (JRE) on the server . So he performed a clean install of Java (which is now I guess the JRE 7) and now the Minecraft server runs flawlessly !!! (I'm trying to get more info from him about the involved Java JRE versions to share)
 * So my ultimate advice is to update Java. Nihilys 10:54, 6 March 2012 (UTC)
 * If you can't make the system (through PATH) run the latest JRE (there can be several JRE available, and an older one in use by default) on the computer just completely uninstall Java and install it back (I wouldn't recommend such action on a production server...) Nihilys 10:55, 6 March 2012 (UTC)

U server crashes after placing lava at level 255. 2012-03-04 12:38:31 [INFO] Starting minecraft server version 1.2.2 2012-03-04 12:38:31 [INFO] Loading properties 2012-03-04 12:38:31 [INFO] Starting Minecraft server on 5.89.12.250:25565 2012-03-04 12:38:31 [INFO] Preparing level "world1" 2012-03-04 12:38:31 [INFO] Default game type: 0 2012-03-04 12:38:31 [INFO] Preparing start region for level 0 2012-03-04 12:38:32 [INFO] Done (919509169ns)! For help, type "help" or "?" 2012-03-04 12:38:34 [INFO] wisenski [/5.89.12.250:62604] logged in with entity id 256 at (152.79105199478292, 256.9910380775109, -244.78650970272875) 2012-03-04 12:38:36 [SEVERE] Unexpected exception java.lang.ArrayIndexOutOfBoundsException: 32768 at gd.b(SourceFile:2192) at gd.v(SourceFile:2076) at gd.k(SourceFile:1919) at gd.l(SourceFile:1958) at gd.h(SourceFile:1795) at net.minecraft.server.MinecraftServer.w(SourceFile:426) at net.minecraft.server.MinecraftServer.run(SourceFile:356) at dm.run(SourceFile:490)
 * This was fixed in 1.2.3. You're running 1.2.2. Please upgrade. Dinnerbone 21:47, 4 March 2012 (UTC)

!! after deleting minecraft.jar to get rid of mods i get on minecraft and it freezes at: updating minecraft. please help.
 * Usually, in order to fix this, you have to delete everything that is in the bin folder. It will then re-download everything.
 * This could be due to the "Java 7" problem that some users have. Try uninstalling any/all forms of Java 7 you have.

a! 1.2.x is unplayable for me on "far" view distance: the game freezes up so much it's like ten seconds of freezing to one second of moving. On the F3 View the graph spikes right up to the top of the screen or off. I am playing with 32 bit Java and I have noted the warning, but there was no freezing or problems until MC 1.2. Is this just because of the new height limit and something I should accept? 90.211.114.219 16:46, 3 March 2012 (UTC)
 * From what I've gathered, it does seem to be mostly attributed to the height limit since it gets to render 128 more blocks per square. Still, I'm sure there will be fixes possible and hopefully soon. Hesuchia 19:06, 3 March 2012 (UTC)
 * I wrote about that as a major bug. "Minecraft is lagging heavily after playing for a few minutes. 0 FPS for 2-4 seconds with >1 sec delay between them. (SP, Normal/Far view distance)". It can be also related to the jungle biome - I have spawned near there. -- L.K.

!! When moving the camera towards a block that was not initially on the camera (eg a block behind you, or a block in the sky) the game may crash without an error log. (I use 32bit Windows 7 and 32bit Java) Update: Made a video of it happening, sorry for the quality. Click here Update 2: Turns out it works on SMP too... Got a neat crash log

18:14:42 [SEVERE] java.net.SocketException: Connection reset by peer: socket write error 18:14:42 [SEVERE]      at java.net.SocketOutputStream.socketWrite0(Native Method) 18:14:42 [SEVERE]      at java.net.SocketOutputStream.socketWrite(Unknown Source) 18:14:43 [SEVERE]      at java.net.SocketOutputStream.write(Unknown Source) 18:14:43 [SEVERE]      at java.io.BufferedOutputStream.flushBuffer(Unknown Source) 18:14:43 [SEVERE]      at java.io.BufferedOutputStream.flush(Unknown Source) 18:14:43 [SEVERE]      at java.io.DataOutputStream.flush(Unknown Source) 18:14:43 [SEVERE]      at net.minecraft.server.NetworkWriterThread.run(SourceFile:103) 18:14:43 [SEVERE] java.net.SocketException: Connection reset by peer: socket write error 18:14:43 [SEVERE]      at java.net.SocketOutputStream.socketWrite0(Native Method) 18:14:43 [INFO] ███████ lost connection: disconnect.endOfStream 18:14:43 [SEVERE]      at java.net.SocketOutputStream.socketWrite(Unknown Source) 18:14:43 [SEVERE]      at java.net.SocketOutputStream.write(Unknown Source) 18:14:43 [SEVERE]      at java.io.BufferedOutputStream.flushBuffer(Unknown Source) 18:14:43 [SEVERE]      at java.io.BufferedOutputStream.flush(Unknown Source) 18:14:43 [SEVERE]      at java.io.DataOutputStream.flush(Unknown Source) 18:14:43 [SEVERE]      at net.minecraft.server.NetworkWriterThread.run(SourceFile:103) 18:16:00 [INFO] /███.███.███.██:█████ lost connection

! Game lags when in jungle biomes and/or around jungle trees.

!! Minecraft will not run with any form of Java 7
 * Apparently I have Java 7 installed and minecraft runs for me. ZuppaHD
 * Runs fine here, too. butterfly98901
 * Latest Java 7 works fine. Tried all combinations of 32bit, 64bit, JDK, JRE on both XP and Win7 -- Lucifer_LLS 11:21, 5 March 2012 (UTC)
 * I have java 7 running on 5 computers, CentOS Linux, and windows: XP and 7. All run minecraft fine.
 * This may occur on some computers. I had it some time ago after thinking Java 7 would improve performances greatly... I was wrong, only way to fix it was to uninstall everything Java7 related and install Java6, no problems after this. Note: I'm using a 5 year old Toshiba laptop with Windows Vista TheOtherRetard 13:56, 6 March 2012 (UTC)

!! Pressing the Open texture pack folder button in 1.2.3 will crash the game
 * Not for me (1.2.3), tried renaming texturepacks folder while minecraft was running, retried, still no crash. 194.137.243.226
 * I cannot reproduce this in 1.2.3 vanilla on Windows Vista Home Premium: freshly downloaded and installed, I login and click texture packs and click button "Open texture packs folder" and the expected Windows explorer folder opens. Please give the detailed error message and check your antivirus software in case that is the cause. -- Aurelius 15:28, 2 March 2012 (UTC)
 * Can you please pastebin the error it gives you? Or does the game just close with no error? Dinnerbone 15:55, 2 March 2012 (UTC)
 * I have this bug too. I used windows 7 with 64-bit Java. The game doesn't crash, it just freezes forever 217.120.203.3 18:49, 2 March 2012 (UTC)
 * To those reporting this problem: use a batch file to capture the java output and check the Event log (if on Windows) and post the details at the minecraftforum or the IRC channel at irc://irc.esper.net/MineCraftHelp so others can help diagnose the cause. Do the usual first: uninstall all Java and install only Java 6; set antivirus and firewall to allow java access to internet and to the %APPDATA% folder; if Windows, check the access permissions. -- Aurelius 12:34, 3 March 2012 (UTC)
 * Yes, that is exactly the problem: minecraft doesn't give an error, and doesn't crash (And yes I know how to run from batch). So I understand that you can't help without logs, I just wanted to say there are more people with this problem. 217.120.203.3 22:18, 3 March 2012 (UTC)
 * Vanilla Minecraft 1.2.3 with no mods? What operating system and Java version? Use a batch file setting APPDATA to make a completely clean install in a separate folder with nothing added and see if the problem reproduces. If it does then this has got to be a system issue, try make a new Windows profile and retest. -Aurelius 04:25, 4 March 2012 (UTC)


 * This sometimes happens to me. Instead of crashing, the game automatically closes without notice sometimes.
 * Can't reproduce on MC 1.2.3 vanilla and *original* Win 7 Professional 32-bit -- L.K.

!! Worlds made before Minecraft 1.2.2 become unplayable. Worlds made during 1.2.2 or after run smoothly.
 * Java and video drives are up to date. 75.106.37.15 21:44, 2 March 2012 (UTC)
 * Update: I don't know how to get the crash report. I wish that I did though. But I can tell you that I haven't used any mods, no world editors, and the world that I want to use was created in 12w8a, others go back to Beta 1.8. 75.106.37.15 02:39, 4 March 2012 (UTC)
 * Update: www.mediafire.com/?4x621niodo5v326 <-- My downloadable world. Made on 12w8a, used WorldPainter to edit the world, and no mods were used. 75.106.37.15 19:39, 4 March 2012 (UTC)
 * Please define "unplayable".
 * Unplayable: During the loading of an older world, it states that it's "switching levels." Then the text disappears and goes to a black screen. 75.106.37.15 06:16, 3 March 2012 (UTC)


 * mp I am not the reporter of this bug, but I am having this issue with the server and ONLY the server version of 1.2.* I have a world from before 1.2 that when converted by the server code spits out this error on a player connecting. When converted for single player use it works perfectly fine. UPDATE: I seem to have discovered this is due to corrupted information in the player.dat file. I am reluctant to upload an example of this file because I do not know what is stored there. My best guess is that it is due to the use of the Multiverse bukkit plugin, as when the world was converted my user was not in the "normal" world. Deleting the relevant player.dat file allows the user to log back in.

[WARNING] Failed to handle packet: java.lang.NullPointerException java.lang.NullPointerException at je.c(SourceFile:102) at ht.b(SourceFile:127) at ht.a(SourceFile:38) at fj.a(SourceFile:94) at net.minecraft.server.MinecraftServer.w(SourceFile:435) at net.minecraft.server.MinecraftServer.run(SourceFile:356) at dm.run(SourceFile:490)
 * To those reporting problems converting pre-1.2.3 worlds please link to the affected world file, and if possible to its archive before it was converted, so that others can help diagnose the cause. Specify how the pre-1.2.3 world was created - which minecraft versions, options, which mods or world editors used. -Aurelius 12:34, 3 March 2012 (UTC)
 * Could you please reword this so that other people that have no idea what you're saying can understand it. 75.106.37.15 21:43, 3 March 2012 (UTC)
 * Zip the problem world folder from the /saves/ folder and upload it to a site such as mediafire, post the URL of the upload here or in a forum. Give details how the world was made, especially if mods or snapshots or prereleases were used in that world history. A mod or prerelease snapshot might have caused a problem. -Aurelius 04:34, 4 March 2012 (UTC)
 * I've uploaded my world that I'm wanting to use. The link is up above with the information. 75.106.37.15 03:40, 5 March 2012 (UTC)

N mp Setting server build limit to 64 will disallow creation of new blocks above 64, but does not prevent loading/generating blocks beyond 64. 194.137.243.226
 * But I think this is good, allows creating areas which are prohibited from modification. 194.137.243.226
 * This sounds like more of a feature than a bug to me. After all, it is called "build limit" and not "generation limit". I believe the intention of this limit is to inhibit player placed blocks only.CaMoreno3 18:21, 2 March 2012 (UTC)
 * Feature, not a bug: As of Server.properties : "max-build-height: The maximum height in which building is allowed. Terrain may still naturally generate above a low height limit. "

!! Maps in SMP tend to overload servers, causing annoying crashes of client and server.

!!mpwhen connecting to a server the client disconnects after 0-5 seconds giving a "connection reset by peer" error,occasionally gives up to 50 seconds before disconnecting happens only in 1.2.3 did not occur in the short window of 1.2.2 or 1.2

! Sometimes in Hardcore mode, if you jump into a ceiling, or walk into walls, you will go THROUGH the walls, and take damage. This also happens with doors, and torches, if you walk into them, you go into them, and take damage.
 * This sounds like an existing bug that happens when your sleep is interrupted by destruction of the bed, or something like that (I haven't seen it myself). It's not specific to Hardcore mode. kpreid

!! When converting (CNB's 3x3 Piston door map that I downloaded) old worlds the game crashes. Black Screen, "Saving Chunks" error does not show for game crashed as world started to convert. ZuppaHD

u Silverfish spawning from being called out of their blocks crashes the game. (please confirm)ZuppaHD
 * Can't reproduce. If it happens again, please let me know what the crash is (error messages/does it just freeze up/etc) and if it's multiplayer or not. Dinnerbone 18:30, 4 March 2012 (UTC)

! (commonly)  (rarely) At extremely low framerates (e.g. 4-6) it becomes impossible to use Mouse1 to attack/mine (brings up ingame menu) tested NOT mouse with a 2button PS/2 mouse. Indrora 04:23, 4 March 2012 (UTC)

!! I was playing Minecraft and suddenly, power failure. Then my world is no longer selectable but its file is still in .minecraft/saves with "level.dat_mcr" missing. (PS : if you know a way to repare it, please tell me)Missingno 26 10:58, 5 March 2012 (UTC)

!!I tried to convert my flatgrass map to Anvil but it just blinks to the convert screen then shows an empty dirt background. After that it kicks me out of fullscreen and shows a black screen. Any ideas? Also I successfully converted all my other super-flat and normal worlds in about ten seconds. This is 1.2.2 and 1.2.3 with no mods and the map's files look identical to the other before conversion, right down to the individual files in each folder. EX: data has the maps and idcounts.dat etc.--Droid1134 01:16, 3 March 2012 (UTC)
 * Can you please try the same map (before conversion) in a multiplayer server, and see if it gives you any errors? Dinnerbone 04:45, 3 March 2012 (UTC)
 * Got this error: (Note: as a half-idea half-just to see if it worked, I did try deleting the top layer of the map; considering the huge bugs related to map height)

[INFO] Starting minecraft server version 1.2.3 [INFO] Loading properties [INFO] Starting Minecraft server on *:25565 [INFO] Preparing level "world" [INFO] Converting map! [SEVERE] Unexpected exception java.lang.ClassCastException: qx cannot be cast to nt 	at pf.g(SourceFile:113) at us.a(SourceFile:27) at ix.a(SourceFile:199) at ix.a(SourceFile:169) at ix.a(SourceFile:128) at net.minecraft.server.MinecraftServer.a(SourceFile:210) at net.minecraft.server.MinecraftServer.s(SourceFile:188) at net.minecraft.server.MinecraftServer.run(SourceFile:333) at dm.run(SourceFile:490) --Droid1134 22:37, 3 March 2012 (UTC)
 * Made a discovery: if I delete all of the region files the world converts but all the world is resetted to its seed. That means that there is a region error. Interesting, but not very useful, unless there is an idea someone has?  Anyone?  --Droid1134 01:48, 5 March 2012 (UTC)
 * I've the same problem with [this map]. See [my pastebin]. --Pyraah 08:03, 5 March 2012 (UTC)
 * After extensive trial and error I have determined that while I can delete certain region files to raise the number of regions converted(ex. I deleted r.-1.-1.mcr and I converted nearly half the regions, but when I deleted r.1.1.mcr in addition, I only converted 3 regions...(after replacing the region files to .mcr)), only deleting all of them will result in a successful full conversion. Which means: saving your world, at least manually, at this point is impossible...  VERY depressing...  I am now trying to use MCedit to transfer my stuff over, but I have no idea if it will convert the new world afterwords.  --Droid1134 03:04, 6 March 2012 (UTC)

Annoyances

a! Starting minecraft in a terminal reveals that 1.2.3 still has a few debug messages. This would not be a problem except that in low-light areas (such as the Nether) a large number of messages similar to the following will scroll by as the player enters a new chunk: "Checking light -13, 14". This is a *huge* performance drain on lower-end systems. It can be somewhat mitigated by redirecting standard output to the bit bucket, i.e., java -Xmx2048M -Xms512M -cp minecraft.jar net.minecraft.LauncherFrame > /dev/null. There is still some performance lag with the light recalculation, but it's a minor stutter as compared to the slideshow without this workaround. --Benanov 06:01, 3 March 2012 (UTC)
 * My FPS drops down to 0 when I am in the nether due to the lighting checks even with this "fix" it still drops down to 0. This is a major annoyance that ruins gameplay on the "low-end" computers/laptops. (I am on windows and I launch with .bat files so this is not linux only.(I changed it)) Kukelekuuk00

a Neither 1.2.3 nor 1.2.2 accept command line arguments that previous versions accepted. I first determined this changed when the minecraft.jar launcher changed from 1.1 to 1.2.2, while the launcher for 1.2.3 is unchanged from 1.2.2. See Stand alone client (change). Please note this is not related to the environment variable JAVA_OPTIONS. -Aurelius 15:22, 2 March 2012 (UTC)

a Holding a map in hand and walking into a jungle biome in a multiplayer server will kick you from the server and produce the message "Internal Server Error". I've only tried it in multiplayer, not sure if it does this in singleplayer.
 * Can you please pastebin the error that is displayed on the server? Dinnerbone 04:34, 3 March 2012 (UTC)

amp Attempting to break the bottom half wooden door while standing in it will result in the door rapidly opening and closing. This can be fixed by moving out of the door.
 * Even if this didn't have a fix it's not a major annoyance --Moxxy 20:04, 3 March 2012 (UTC)

a under Java6-sun on Ubuntu (Untested on other distros) pressing "return to game" from the menu does **not** trap focus of mouse (Esc does though) Indrora 04:23, 4 March 2012 (UTC)

!! Alot of times when going into fullscreen, the game crashes, and leaves a crash report. The ammount of times this happens can be reduced when turning on Power Saver, but then it still happens. I do know this doesn't happen for everyone.

a  Cmd-Q don't work (should quit the program). Not even on main screen. 86.50.91.240 13:57, 4 March 2012 (UTC)

a I don't know if this happens to anyone else. But whether on Single- or Multi- player my computer freezes up every 15 minutes or so. I hae to ctrl + alt+ dlt to exit out.. Also my commands don't work so i don't know if it's the server or a bug. AidynsMommy

a Certain areas can take a lot of CPU (90%+) in the "Tick" (according to F3) which causes that area to be unplayable. Terminal output is littered with the following messages, which generate until the affected area is fully loaded/drawn, but the high tick CPU still remains. root.tick 132690891 root.tick 128422656 root.tick 127943228 root.tick 128478097 root.tick 128645844 root.tick 127838412 root 786382821 803090124 root.tick 130718535 root.tick 130720120 root.tick 128171555 etc. --Benanov 00:25, 7 March 2012 (UTC)

Redstone
Bugs ! Redstone torches eventually burn out on all known T flip-flop designs, including both regular and piston-based. Once burned out, they instantly re-burn out when replaced, making it impossible to create a stable T flip-flop. Seems to affect some worlds, but not others; try it in the seed "indianajones" (generated in 1.2.3). Tested repeatedly in multiple chunks, and ruled out the north-south bug as a cause. --Tigerstripe

! Redstone does not power redstone placed below when placed on glowstone.
 * This is not considered a bug by many people, as it is more of a feature, allowing one-way redstone. -- Zugbug

undefined A redstone torch placed one block over and one block above a slanted powered rail has no effect in 1.2.3. In 12w08a and previous versions this powers the rail.
 * A torch shouldn't be able to power a diagonally-adjacent block. If there's a bug here, it's that the rail was powered in previous versions. -- Orthotope
 * I'm pretty sure powering rails through the block above them was an intentional feature. It may have been intentionally removed, but I've never heard anything about that. –Preceding unsigned comment was added by Last username (Talk&#124;Contribs) . Please sign your posts with
 * A torch directly above does power rails (and everything else), as it should. In the screenshot, the torch is not above or horizontally adjacent to the rails, so it doesn't power them. Again, this is not a bug. -- Orthotope

!MP When powering a redstone torch to turn it off and then unpowering it to turn it on it will sometimes begin to stay off until you replace it, however it will immediately repeat this behavior the moment it is powered again forcing the need to replace it each and every time until it is moved to a completely different location at least 5 blocks away from where it originally was set. This only seems to happen in Multiplayer as I have not been able to recreate it in Singleplayer.
 * A Redstone Torch should be powered when not powered and not powered when powered -- Cyan4235
 * This happens only in multiplayer, and only when you adjust the time of day using the "/set time" command. -- Fizzster 08:18, 5 March 2012 (UTC)
 * Currently I have this issue on my server, it is happining even though the time has not been changed.
 * This beg seems to be related to the server using lots more ram when redstone is running, my server jumps from 33mb to 52mb in just under 10 seconds after starting a clock.
 * Had similar issue in creative mode single player. Did not notice it immediately but once it happened it continued to happen regardless of map; however, only in creative mode. Had to change the location to get redstone torch to work, but did not need to move 5 blocks. Get about 7 or 8 uses out of a torch before it failed to activate. The number of torches, direction, and frequency did not seem to matter. Appears to be the same bug as the first bug in the redstone section.

undefined When you quit and reload a game, redstone repeater loops freeze.
 * Are you sure?? This sounds awfully like the old Repeater Persistance Bug, which was fixed in one of the Beta 1.9 prereleases.  Please verify that you are using 1.2.3.  Also, I have refiled this issue as a bug, since it describes a (potential) bug.  Annoyances are for non-bugs only.  &mdash;Immute [talk]
 * Having same problem on a server.

undefined When the block below a repeater is removed that is currently powered on, the redstone wire on top of the block that the repeater "points" into remains powered after the repeater is removed. From my own findings it works both in single player and SMP. -- Bartvbl

Annoyances

a! Piston bug: stacking two pistons on top of each other (both pointed sideways), then powering the top one by placing a block on TOP of it with an active redstone wire, will power the top piston normally. If the block BELOW the 2-piston stack is removed, the bottom piston activates, and mysteriously receives power through the adjacent piston, from the wire 2-blocks away. Getting this bottom piston to turn off is nearly impossible, as replacing that block does not sever the ghost power source. The power is persistent: the bottom piston can be removed and replaced, and will immediately be powered. Powering/unpowering the bottom piston directly has no effect, and it cannot be retracted once glitched. Easily reproduced on two separate computers (in survival/creative single-player). --Tigerstripe
 * The phantom power seems to be related to the upper piston being extended: once glitched, the bottom piston can only be retracted once the top one is also retracted... so it's as if an extended piston's base transmits power vertically downward, as redstone wire does horizontally. --Tigerstripe
 * The piston is definitely glitched. I removed all blocks around the piston, and it floats in the air, extended. --Tigerstripe
 * Most likely an effect of the Piston Quasiconnectivity Bug --Variable

a In certain places some pistons will not shut off even after power is removed. It requires a block update to fix.

a Redstone repeaters may increase the length of short pulses(one to three ticks) of power. When the delay setting on a repeater is a larger number of ticks than the incoming pulse, the outgoing pulse is increased to the length of the delay. For instance, a one-tick pulse of power going into a four-tick repeater will output a four tick pulse of power. Can be reproduced using a one-tick pulse generator followed by five one-tick repeaters. Then change the delay on the first repeater in the series to the desired pulse length.

a I am not sure if this was intended or not but pressure plates are no longer activated by dropped items or fishing rods. Chillywindy 21:50, 6 March 2012 (UTC)Chillywindy

Blocks
Bugs

x There is a bug that can be used to change the damage value of blocks. http://www.youtube.com/watch?v=EgUTtTg_IiA

x Vines are replaced when a block is placed in the same space as them, like water, lava, snow, and grass. This is annoying and does not fit well with their new functionality.
 * That's not a bug, that's very useful ! If you need the "new functionality" then place ladders.... 80.134.16.11

! The old bug with wrong tools for blocks. for instance pickaxe is quicker for removing wooden halfslabs --86.52.2.125 12:59, 3 March 2012 (UTC)
 * This is technically not a bug; the cause is that all slabs are differently skinned versions of the same item. All other slabs are material types mined with picks, so the wooden slab's item data sets it to be mined with a pick. This should still be fixed, though. 208.58.177.214 19:01, 5 March 2012 (UTC)

!! Previous world converted, now when placing blocks Minecraft crashes. When re-opened the block is still in your inventory and in the world. Only some worlds.
 * Error occurs to me as well but I relate this to a Lightning bug. I tested it with "Super Hostile - Spellbound Caves v1.1" see [Link]. Error Report in the description. --LordJakson 21:04, 2 March 2012 (UTC)
 * Confirmed on our map (SMP, converted from 1.1). While building a sculpture out of blocks, occasionally the client (and sometimes the server) crashes with "Internal server error".  When I log back in, the lighting is . . . odd looking, though I can't quite put my finger on what's wrong with it.  This has happened when placing cobble, pistons, and water from water buckets (the type of block may not be relevant).  In each case, I was placing blocks in a fairly confined space where the lighting calculations might be more complicated than normal, but I haven't looked at the lighting code since mid-Beta.  Haven't tried building on a 1.2-generated map; the players are somewhat invested in the current world.  Blahpers 20:55, 3 March 2012 (UTC)

!! (Unconfirmed/not thoroughly tested) Placing a torch (potentially other items?) on y=257 -- one block above the height limit -- is allowed, but in SMP causes an "Array out of bounds" exception and crashes all connected clients in addition to the server, requiring a server restart.
 * I actually created something similar in single player. Built tower to max height, placed water on top (technically above) and then replaced water with torch.  crashed immediately. (EDIT seems to have been fixed in 1.2.3)-- Kittani1977
 * Still reproducible on 1.2.3 SMP --Outi 09:51, 2 March 2012 (UTC)
 * (1.2.3 cmp,smp) I was able to place torch there, but no crash. 194.137.243.226
 * Please pastebin the full error you get so that I may investigate it. Dinnerbone 19:07, 2 March 2012 (UTC)

! Having a tower to the max height to 256 in the sky, and having a ladder on the side from 1-127 will show just fine, but 128-256 will be invisible. Breaking any one of the invisible ladders will cause all of the invisible ones to break and fall down as items. Visible ladders from 1-127 work just fine though.

undefined When an upside down stair is placed on a grass block, the grass block will eventually turn into a dirt block.

undefined you can't grow birch and pine trees over 128 block high. oak and jungle tree grow just fine with both versions available.
 * I was able to grow both at 140+ with bonemeal, may have been repaired in 1.2.3 --Kittani1977
 * Was able to let natuarally grow all trees at above 128. A 2x2 jungle tree grew up to within 2 of the top level with bonemeal and a single jungle grew short to the same point in 1.2.3 -- Kittani1977

undefined Piston arms no longer are able to push the player in single player. can be "fixed" by shooting an arrow into an extended piston head in a nearby loaded chunk (effectively breaking compact 4x4 piston elevators)

! Jungle tree leaves rarely ever drop jungle saplings.
 * I believe this is because they only drop saplings when a player breaks them. Could someone confirm? Regdoug 23:42, 3 March 2012 (UTC)
 * No, they drop saplings regardless of whether being broken or decaying. I have been farming a lot of jungle trees for saplings, so I can say for certain that although the drop rate is low, it is definitely renewable (though it is a little annoying when I go through six trees and end up with one fewer sapling than when I started). -Thorny 09:38, 4 March 2012 (UTC)

xcr When a door is broken by clicking on the top half, the item drop appears. Breaking the door from the bottom doesn't do this, however.

x glowstone will not stop a chest from opening.(tested on windows 7)
 * As glowstone is not a solid block, I believe this is expected behavior. 109.246.254.186

f If you destroy a painting while on sprint you get two drops instead of one

undefined Grass continues to spread to other blocks even with another (even non-transparent) block on top of it. Grass also either seems to take a long time to revert to dirt with a block on top, or never reverts to dirt at all. Prior to this bug being introduced in 1.1 or 1.2, grass never spread if there was an opaque block on top of it.

Annoyances

a Mossy Cobblestone still uses the old cobblestone's pattern

a When you try walking on jungle leaves diagonally or near a hole, sometimes you will fall through the leaf, possibly dropping all the way down if there's nothing below it.

a When you try to cross ANY hole when 1) there is a ceiling over it and 2) block is diagonally touching to the hole like this: [#][2] [1] [#] = wall/pilar/obstacle, [ ] = ground, [1] = you are here, [2] = you want to go there You have 50% to fall down into the hole - you fall if walking in one direction (eg. 1 to 2), but not in the other (2 to 1).178.180.3.80 00:34, 6 March 2012 (UTC)

a You CAN press "Shift" when you're sleeping on bed.

a You cant place torches on the bottom of blocks
 * You're not supposed to be able to do that.
 * Agreed, you are not supposed to be able to do this. Requesting removal --Moxxy 17:57, 4 March 2012 (UTC)
 * (From original poster) Well you can place slabs and stairs upside down. I know you aren't supposed to be able to that's why I marked it as an annoyance. And not a bug. It is annoying that you cant place torches on the bottom of blocks.
 * Just because two items were made to be placed upside down does not mean every item that doesn't is an annoyance. It doesn't even make sense, torches don't work that way! --Moxxy 23:11, 4 March 2012 (UTC)

a This is likely an intended effect, but sticky pistons cannot grab other pistons
 * They are supposed to be able to do that - if the other piston is retracted. Tested it in creative 1.2.3 - it works (if retracted, it doesn't work if they are extended - as it should be). Please recheck whether it works on retracted pistons. If not, it's a bug and should be reported as such. --Bodo Thiesen 01:31, 7 March 2012 (UTC)

Crafting/Enchanting/Brewing/Interface
Bugs !Silk Touch doesn't work on Glass Blocks anymore.
 * If you mean Glass BLOCKS (result of smelting sand in a furnace) then this is a bug. If you meant Glass PANES (created by crafting 6 glass together in a workbench), then that is normal behavior. --Nathan2055 22:51, 2 March 2012 (UTC)
 * No, Silk Touch really doesn't work on glass blocks anymore. Almost certainly unintended, especially considering that Jeb wanted to take a look at ice functionality again.
 * On reddit Jeb found out about this and confirmed the glass thing is a bug.
 * Confirmed. This is a bug, and I have upgraded it to major. &mdash;Immute [talk]

u The first character of every enchantment label is missing. For example, "lame I" instead of "Flame I".
 * Grammar corrected for clarity. CaMoreno3 19:21, 1 March 2012 (UTC)
 * Appears to have been fixed in 1.2.3, but now cannot seem to get any enchantment to show up over 39 (EDIT: Been messing with it for a while to confirm.. it seems ok... but different... somone else is going to have to do this too. -- Kittani1977
 * Can't reproduce. If this happens again, please let me know what language you're using. Dinnerbone 01:16, 4 March 2012 (UTC)
 * The cause is from TooManyItems. Within 1 hour, Marglyph reuploaded the mod and addressed this. Goandgoo 01:48, 4 March 2012 (UTC)
 * I wasn't using Too Many Items but I have noticed enchantments showing up over level 40 is far less common, even with the proper Bookshelf array. I spent nearly an hour clicking through on a diamond pickaxe and only saw 50 twice, 49 maybe 3 times, I either have the worst luck or the rare levels for enchantments are now even rarer.  Fine by me but it's noteworthy as I said for at least a glance at the code to make sure that it's still set right.  Those random item generators can get really wonky sometimes. -- Kittani1977

fEnchanted items in a minecart with chest lose their enchantment when the minecart with chest get's "destroyed".

Annoyances

a! The enchanting system has always, and continues to be frustratingly unfair. sometimes producing Efficiency III when a level 50 enchant is used. Considering you need to kill NINE HUNDRED AND TWENTY FIVE zombies/creepers etc, to get to Level 50, users are naturally in consensus that, to quote Yahtzee Croshaw, the ratio of difficulty to find versus actual usefulness is completely arbitrary. While we respect the mystique Mojang have tried to create about enchanting, the numbers need serious review. Kizzycocoa
 * Discussion moved to this page. Please comment on that page.

a In the Multiplayer server list, we can connect to a server by selecting it and pressing enter. In the Singleplayer world list, pressing enter will do nothing.

a Signs don't stack in inventory. (Trenix 22:16, 4 March 2012 (UTC))
 * I find this extremely annoying as well. Now, before anyone claims "not a bug", let me point out that this issue was filed as an annoyance. Annoyances are, by definition (see the instructions above), precisely those issues which are not bugs. &mdash;Immute [talk]

a A very old bug annoyance: When Lava Buckets are used as fuel for smelting, the bucket is consumed along with the lava.
 * This is expected. See the lava bucket page. Magnumm6 16:26, 4 March 2012 (UTC)
 * Yep. Not a bug; refiling as minor annoyance. &mdash;Immute [talk]

a On some systems, pressing the mouse 4 or mouse 5 buttons on the side of the mouse will cause the Minecraft menu open.

a While in fullscreen mode (through F11), opening any menu (inventory, options, etc...) will cause the mouse to jump position.
 * Actually is does not jump but is moved to the center of the window (it is moved off-screen while the target marker is visible). Problem is, that the center of the window and the center of the screen are not the same positions... 95.208.228.252 18:32, 6 March 2012 (UTC)

a "where are we now" music disc is still missing (should be at least in the creative inventory).

a Wooden tools cannot be used as fuel in a furnace. If they could, then they would be helpful for smelting your first charcoal after you don't need wooden tools anymore.
 * This is a neat suggestion. I like it. &mdash;Immute [talk]

a Though this is likely intended, jungles will often spawn with regular (oak) leaves rather than jungle leaves. This means they don't drop jungle saplings which will grow into large trees instead of the regular trees.

Gameplay
Bugs

? When crouching and backing up to place a block, you can place a block on the space where you are standing. This makes it so that you will fall when you release shift, as you can't jump around the placed block or place another beneath you to stand on. So far I've seen this only happens with cobblestone, and I have tested wooden planks, stone bricks and netherrack. This may not happen with other blocks.

! Mobs and the player can breathe in lava, unlike in Water. This is probably unintended behavior and was likely never tested because before the Fire Resistance potion was added nobody could survive long enough to see if the bubbles would show up. And yes, I tested this in Survival Mode.

undefinedWhen entering the game, the player may end up at a higher vertical location than where they left. -- Firrox 4 March 2012

undefinedGoing through a Nether-Portal creates a new Portal in Nether over 126- so over Bedrock - It happened to me on my server when my old one in nether was destroyed. I just copied the new server exe, so that the world data were the old from before 1.2.3.
 * Not a critical, game-crashing bug; downgraded. -- Orthotope

!Falling into the void is non-lethal in creative, switching to survival does not fix this (TMI was installed to change gamemodes after falling for an hour).
 * Could not reproduce on either creative or survival.

! cr This old bug has been around for as long as Creative Mode itself. When flying in water or lava, horizontal movement is slowed to a crawl.

! Vertical momentum is maintained when traveling through an End Portal so falling into one can kill players in the End.

! When colliding with soul sand in a boat, as soon as the player collision box crosses the soul sand collision box, the player will take fall damage equal the velocity at which the boat originally approached the soul sand. Easy to reproduce. Flagged major because soul sand as protection against boat destruction is a long-standing convention and death in situations where you wouldn't expect to die is kind of a deal breaker. --TQuin
 * Upgrading to major bug—I seriously doubt this is intended behavior. 109.246.254.186

x mp Naturally generated leaves no longer decay in 1.2.3 tested in vanilla SMP
 * All naturally generated tree leave types decayed. (oak, large oak, birch, pine, jungle tree, 2x2 jungle tree, jungle undergrowth tree) (tested in cmp) Did this occur at 1.2.3 generated world or converted world? 194.137.243.226
 * It was a 1.2.3 generated world.

u Right-clicking with a water bucket will crash the game rarely. -FishSticks -Unable to reproduce
 * Could not reproduce with over 300 buckets placed in 1.2.3 -- Kittani1977
 * Can't reproduce. If it happens again, pastebin the error please. Dinnerbone 04:49, 3 March 2012 (UTC)

undefined While swimming through water surrounding blocks of water will turn to a darker shade of blue, these darker spots do no revert when you touch land and end up making the area look shoddy and generally ugly.
 * Does not appear to be happening in 1.2.3 -- Kittani1977
 * Happened to me as well, especially when I placed and removed blocks in moving water. -- sk9c00

undefined Chests seem to get caught in an endless loop of opening and closing.
 * Could not reproduce in 1.2.3 -- Kittani1977
 * This is happening but may be multi-player only -- Alexander
 * Should this not be a Major Annoyance a!? -- (Txtsd 07:10, 5 March 2012 (UTC))
 * Happens to some people some of the time on my SMP server, at least while they have the chest screen open - Lucifer_LLS http://www.lowlifescum.com 10:23, 5 March 2012 (UTC)

undefined If you log out while sitting in a boat, you fall out of the boat when you log back in. 82.69.54.207

u Doors will not open for non-ops in vanilla SMP
 * Could not reproduce with 10 different players. was it inside the protected spawn area? ~Ramena
 * A player on my server reported this as well; had her re-log, to no effect. Ended up destroying the doors in question and replacing them, which apparently fixed the issue. No clue what happened there. The area she experienced the problem in had been ported from 1.1 to 1.2 via MCEdit, leading me to believe it has something to do with doors not properly converted to the new standard. --Chromium 22:55, 4 March 2012 (UTC)

! mp Upgrading an unmodded SMP server from 1.1 caused the previously-developed Nether dimension to regenerate from scratch, destroying all player creations. Blahpers 21:32, 2 March 2012 (UTC)
 * Unconfirmed on a server I go on. We are an unmodded server, upgraded from 1.1, and our Nether is still intact. Zyn 22:15, 2 March 2012 (UTC)
 * Must be one of those fun intermittent bugs. There are several posts about this on minecraftforum.net regarding this behavior in 1.2.2.  Digging them up now. Blahpers 23:21, 2 March 2012 (UTC)
 * Here: http://www.minecraftforum.net/topic/1068277-nether-not-converted/ Blahpers 23:21, 2 March 2012 (UTC)
 * Confirmed on a modded server I go on. Additionally, the nether was very laggy, while the overworld wasn't.
 * I am also experiencing 1.2.3 creating new anvil data rather than converting existing nether regions. Both with vanilla server and with latest bukkit.

a In SSP,the game seems to be laggier than it used to,but in SMP there's barely any lag.
 * This is a system issue, not a bug with Minecraft. --Nathan2055 22:51, 2 March 2012 (UTC)
 * I've had the same problem. However, I used to get around 90 to 120 FPS, now about 60. I also drop to the 30s when I look the directions f: 2 and f: 3 (like Minecraft's ingame compass without redstone if you press F3). However on some servers (ex. evocraft.net) get the average 80 when looking all ways) also looking up and down shoots my FPS up to 250 to 300. (1.2.2, 1.2.3) My seed is JUNGLEHUNT if you're wondering. Edit: It is a problem with jungles. If you are near or in a jungle, facing a few ways will cause you to drop in FPS a bit.

! sp When walking next to redstone repeaters in a room two blocks high you will sometimes fall through the floor, potentially resulting in death from lava, fall damage or suffocation. (This has been around for a while, but it still needs to be addressed.) Dendrite 23:56, 2 March 2012 (UTC)

replicate construction... x=block r=repeater 0=air y level 1 xxx xxx xxx y level 2 xr0 r00 000 y level 3 000 000 000 y level 4 000 0x0 000 Walk towards inside corner of two repeaters. Make sure you have 2 space bellow construction. 93.106.40.21

x Place one jungle sapling and three normal saplings in a 2x2 grid. Apply one bonemeal to jungle sapling. Nothing grows (as expected), but the normal saplings turn into jungle saplings when you break them. 67.255.2.214 07:03, 3 March 2012 (UTC)


 * Actually, this seems to be sporadic. Now a 2x2 tree grows when I apply bonemeal. 67.255.2.214 07:24, 3 March 2012 (UTC)


 * I can clarify this bug - if there is no room for the jungle tree to grow, you will get 4 jungle saplings back instead of what you planted. --Benanov 16:59, 3 March 2012 (UTC)


 * I recreated this bug. It just created a a huge jungle tree. I put the bone meal on the jungle sapling and it turned into a huge jungle tree.


 * The commenter clarified that the sapling needs to be placed in an area where it cannot grow. Also, sign your comments with two dashes and four tildes. --Chromium 02:31, 5 March 2012 (UTC)

undefinedOpening a chest in single player while holding an in-game map deletes in-game map. Not tested in multiplayer.
 * Unable to reproduce. --Lolmaster 06:30, 4 March 2012 (UTC)

! After swimming on a boat on a few half blocks (wooden) being under water I died (in hardcore mode)

undefined The player cannot sprint up stairs.
 * This is completely game breaking and ruins my entire experience of Minecraft... oh wait... no it doesn't. DOWNGRADED! --Moxxy 20:37, 4 March 2012 (UTC)
 * First of all, I can't comfirm this, second, even if it was, I don't think it would ruin the game. TTiscoming 20:47, 4 March 2012 (UTC)
 * Confirmed in SP and MP. Additionally, I remind the above commenters that a bug does not have to be "game breaking" to be a bug. A bug is a divergence from expected behavior in a program. As the player can sprint over slabs, and both slabs and stairs have the same purpose, it seems logical that stairs should allow sprinting, and therefore this would be a bug, if only a minor one.

Re-upgrading. --Chromium 02:31, 5 March 2012 (UTC)
 * May I remind Chronium to read the history of the page before berating other users. This was marked as a Major Annoyance. I never changed it from a bug. --Moxxy 03:31, 5 March 2012 (UTC)

Annoyances

a jungle leaves on 2x2 trees start to decay as soon as they are planted
 * Can't confirm this. Planted 10 2x2 jungle trees and none of the leaves decayed
 * This is the furthest thing from being major. Downgraded, --Moxxy 20:04, 3 March 2012 (UTC)
 * This bug is most noticeable moments after world generation. While observing generated trees in jungle biome, some of the leaves decay immediately.

a Dungeons generate much more often, and most often have only one chest. Yes, you can get more rare loot (saddles, cocoa beans, etc), but the monsters are extremely annoying hands down.
 * Major means it ruins your experience. Downgraded. --Moxxy 20:04, 3 March 2012 (UTC)

a When pressing F3, a graph shows up. It often happens that this graph is too large for me to see my coordinates, seed, biome, etc. The graph just takes too much space. It would be cool if you could toggle the graph or it would be put in the background.

a You're not able to get to an Netherportal over the old build height (If you get into a Portal that is really high, move out of the Netherside Portal and go in again, it will spawn a completly new Portal on the ground.)

a When fire charges travel too far away from the player, they stop moving, but continue to exist in the same spot forever.

a The sound of rain still fails to play in Extreme Hills biomes. It is as if the lack-of-sound associated with snow is there by mistake. This has been an issue since at least 1.0 (the full release).

a! My game has sound files, but will only play the damage and lava sounds. My .minecraft folder is completely untouched and I'm running on a Windows 7. (This has happened since 1.2.1)

a Player looses potion effects when going trough nether portal.

a Some times the player arrow on the map points some degrees to the left. The only way to fix is to rotate your camera clockwise lots of times.

Mobs
Bugs

undefined cr When using dyes on sheep, or bones on wolves, or meat on wolves not at full health, or raw fish on ocelots, they are used up, even though it's Creative Mode.

! Minecarts don't die when they fall into The Void. This can be exploited by griefers to cause lag on servers.

fmp Random instances of the inability to interact with mobs and sometimes boats in SMP. This includes attacking mobs or feeding animals. --Firrox 4 March 2012

undefined sp as of the latest snapshot/1.2.3 npc's don't close doors anymore when you open them, making it possible for zombies to enter the house.

! Once the Enderdragon has been struck by the player once, it can no longer harm the player. This bug has been present for a long time. It can even be replicated in Creative mode, because the Enderdragon "repels" entities in a radius around itself until it is hit, at which point, the player can come in much closer.
 * Furthermore, Endermen have an extremely frequent tendency NOT to teleport, if the player strikes their legs repeatedly with a sword. This is a commonly utilized exploit, usually tossed about as "aiming for their legs". It makes defeating Endermen very easy.

! Very commonly hostile mobs show signs of peacefulness. They won't chase the player and simply walk around minding their own business. However, upon approaching to about two to three blocks away they turn aggressive and begin attacking. I've seen this bug occur with Zombies, Skeletons, and Creepers with 1.2.3 (the latest patch as of writing) installed. --Nathan2055 22:51, 2 March 2012 (UTC)

undefined When a baby pig has a saddle and a player rides on it, the player appears to have four legs. (Trenix 23:45, 5 March 2012 (UTC))

undefined When a Slime is red and starts emitting smoke, logging out of the client and logging back in will freeze the slime in it's current position, but it can still move. --Honeyblue 9:10, 3 March 2012 (EST)

undefined Occasionally Skeletons stop burning for a few seconds upon attacking them. Only confirmed with Skeletons with the latest patch (1.2.3) installed. --Nathan2055 22:51, 2 March 2012 (UTC)

undefined In 1.2.2 Snow golems do not place snow on the ground when wandering around at all.
 * Clarification: They do not place snow in plains, swamps or mushroom biomes. It's still unintended, and should be fixed.
 * Still do not in swamps in 1.2.3, haven't checked others. -- Kittani1977

undefined Snow golems die under snowfall (confirmed by multiple users).

undefined Ocelots only spawn on easy or above difficulty only (Even though they are suppose to be peaceful mobs and don't harm you) Confirm?
 * I believe this due they spawned by mob generator. Read about that on weekly bug pages. (not tested) 194.137.243.226

undefined Passive mobs do not (cannot) spawn in superflat survival mode. I think this is because so many slimes are spawning now the slime spawn rate bug has been fixed, that passives simply never get a chance to appear. Settings: Hardcore, superflat, single player, no buildings, Mac OS 10.5.8. I've now travelled for around 14 game days without seeing one single pig, cow, sheep or chicken. 82.69.54.207 17:14, 4 March 2012 (UTC)

undefined Iron golems do not spawn naturally.
 * Inaccurate. I have had iron golems spawn in my villages since the update.
 * Might be that they don't spawn in villages created before the current version. I've spent a lot of time in a village in one of my older worlds and have seen none.  Can anyone else confirm? --TQuin
 * There must be 15 or more Testificates in an area for them to spawn. Build more houses for the Testificates to live ing, they will reproduce, and eventually one will spawn. Levy 19:25, 4 March 2012 (UTC)

undefined When standing you stand in a portal with a block behind you creepers sometimes won't attack you.
 * Isn't that a good thing? Yoshidude56 17:48, 2 March 2012 (UTC)

? Not sure if this a bug, or an implemented feature, but in Singleplayer or SMP, Hostile Mobs do not spawn above level y: 240.6. This was tested on a newly generated world, and an old world converted to Anvil. - Dirtyfargo

? Iv'e found a village in SSP while using 1.2.3, it started out with 10-ish villagers and now it only contains 3, they have not mated even once, not even the heart particles appeared. i tried this again in creative mode with superflat world, and it still did nothing, this city included more than 30 people and not a single golem spawned. if it matters, i tried this on easy mode. CodyBeach22

undefined Some mobs that shouldn't be able to climb ladders (cows, pigs, sheep -- not chickens, as far as I can tell) can climb them anyway. --Chromium 19:12, 3 March 2012 (UTC)

undefined When a new Slime is spawned naturally or from an egg, xp drop is set to 4, 2 or 1 depending on its size - correct. But when it is loaded with a chunk or spawned from splitting, xp drop is a randomized (but still it's 4, 2 or 1) - incorrect. This bug also applies to Magma Cube. --mgr 23:22, 3 March 2012 (UTC)

undefined mp Large Slimes seem to have incorrect hitboxes at times, perhaps taking on the hitbox of a smaller size of slime. They can still hurt players from just as far away as their size of slime normally would be able to, which makes fighting these glitched large slimes much more difficult than it otherwise would be.

undefined mp On multiplayer, mobs frequently glitch through closed doors, fences, and occasionally walls. Similarly, tamed cats and wolves randomly stop sitting down and begin wandering around again.
 * Can confirm this, had posted similar in Annoyances below.

?Baby animals follow you when you hold wheat.Missingno 26 09:40, 5 March 2012 (UTC)

undefinedmp Attacked Zombie Pigmen will attack all players on a server (instead of the one who attacked them), and will not return to being passive over time.

Annoyances

a There is no way to choose which cat you get. You should be able to feed an ocelot different meats and the breed is determined by the meat. Siamese - fish, tuxedo - chicken, ginger - beef.
 * Why is this necessary? Cats do not have different actions by type, and food to select a cat type is unrealistic.

a Sheep create an unappealing landscape because they're able to turn grass into dirt. Grazing is perfectly fine, however this action needs to have conditions so this annoyance can be manageable.

a Villagers are breeding incessantly.

a Villagers tend to gravitate to a single house and clog the doors. Some are constantly trying to close the door while others are trying to get in. There are plenty of houses available that only occasionally have villagers in them. The mobs generally get stuck until morning and take about half the day to finally work their way out of the jam. The jam occurs every night at nightfall with mobs passing several habitable houses to go back to the same one every night. -- Kittani1977
 * Here's an example in my village. --BillZebub 16:24, 5 March 2012 (UTC) fullhouse.png

a Ocelots are just untameable.
 * You might just be doing it wrong. Are you standing perfectly still? Do you give it fish when it walks up to you cautiously? Are you not looking around really fast? 69.141.106.13 17:53, 3 March 2012 (UTC) CoalSponge
 * Not correct. Ocelots can be tamed very easily. Testing on Creative shows that ocelots that have not been startled will almost always notice held fish within ten seconds.
 * Have had no problem taming ocelots in MP, it just takes patience, and standing completely still.

a Villagers don't know how to climb ladders.

a Pigs are outclassed by cows right now because while pigs only drop 0-2 porkchops, cows drop 1-3 raw beef and are so much more useful in general. There is no good reason to farm pigs rather than cows, and pigs should at least be a reliable source of meat.
 * I agree that pigs should have a 1-3 drop rate, or cows should have a 0-2 drop rate. The two would also be more balanced if saddled pigs could be controlled in some manner.
 * No, no, no. You start this **** in every bug page. Cut it out! --Moxxy 23:13, 4 March 2012 (UTC)
 * Moxxy, I was not aware that you decided what was permissible conversation. I feel obliged to remind you that all users are allowed to converse about bugs and annoyances at will in these pages. You should not try to tell them what to do, as they have the same rights as you do. --Chromium 02:39, 5 March 2012 (UTC)
 * Don't get all high and mighty with me Chromium. I'm telling him this because this has already been discussed to death in many previous bug versions. --Moxxy 03:31, 5 March 2012 (UTC)
 * Irrelevant. Please direct users to the talk page if discussion cannot take place on the main page for any reason, do not tell them to refrain from discussion. --Chromium 05:40, 5 March 2012 (UTC)
 * And there's a long argument on the pages too it seems. Hmm... seems like we should have a section called "Balance Issues" added for these types of suggestions about how the game mechanics should be handled outside of actual Gameplay bugs (IE stuff that may or may not be intentionally done that way for a reason) -- Kittani1977

a Iron Golems do not kill slimes. Slimes are annoying in superflat worlds and should be killed.


 * Slimes aren't just a nuisance, they're a blasted plague, but there are in-game workarounds to reduce the problem. I'll add a tip about it to the slime mob writeup 82.69.54.207


 * I believe this is for 2 reasons: One, the iron golem would be chasing too many slimes and eventually get out of range from the villagers, where they will not be protecting them. Two, they will be distracted by the slimes while villagers will be prone to zombie attacks.

a Ghast's fireballs does not do explosion damage, making ghasts very weak opponents.

aAnimals won't follow their babies.Missingno 26 09:37, 5 March 2012 (UTC)

a!Animals follow you when you hold wheat even when they can't breed, which is annoying when you attempt to breed all your animals.Missingno 26 09:37, 5 March 2012 (UTC)

a!When I updated to 1.2.2, I created a new world. I walked in one direction for a while and noticed a few wolves seemed to be following me. I thought this was odd but continued to walk. After a while, every step would bring a few more wolves. Soon, there were about 30. I wandered into a jungle and dug a small shelter, barely large enough for a bed, and wolves and ocelots soon filled the hole. It was almost impossible to move. After creating another new world, I wandered through a jungle and noticed piles of ocelots appearing inside leaf blocks. It's good that I had kept a backup of 1.1. Shortly after downgrading, I installed 1.2.3. I generated a new world and spawned next to a wolf. Immediately, every step would bring more wolves to me. I knew that this bug was not fixed so I downgraded again. 174.1.45.173 02:30, 3 March 2012 (UTC)

a Not sure, if its a bug or just a feature - the light level necessary to spawn hostile mobs seems to have changed. When it was 7 before, it seems to be raised to 8 now (so, its actually easier for mobs to spawn now). --77.10.60.153 21:10, 6 March 2012 (UTC)

a Villagers trample their own crops. Minecraft5025 23:26, 6 March 2012 (UTC)

World generator
Bugs

undefined Stronghold libraries do not have floors. They should have floors in the same way that abandoned mineshafts do. Right now I have not seen a single Stronghold library which had a floor. Sometimes there will also be no floor under iron doors, and when the button is pressed the door will fall. There are even wooden doors which are not on a floor.

! Village generation is very messy. Ravines, hills, and other stuff can ruin villages and doors can be blocked or stairless in a way that cuts villagers off from the rest of the village.

! Biome "stripes" occurred in my world, destroying the village nearby and causing long, multicolored streaks in the ground for miles. Alternating pattern of swampland and plains. Seed is "tarzan", coordinates are in attached pictures. imgur.com/a/tVeNq
 * Upon restarting our server, the mess fixed itself. (Undo by 80.134.16.158)

! Flat Worlds revert to "normal" when converted to Anvil, new chunks generate as "normal". http://i.imgur.com/mjV7v.jpg

undefined (1.2.3) Chunk generation error, chunk seems flipped. Seed "bug" (without ") location 41x,-381z. 194.137.243.226
 * Added picture Zicxynum 15:57, 2 March 2012 (UTC)
 * Unable to reproduce, running vanilla 1.2.3, using seed "bug" at exact location. Check for mods.
 * That seems to be a basin flooded by water...  Interesting...
 * Really? If this md5 12f6c4b1bdcc63f029e3c088a364b8e4, size 3 988 921 bytes, is not vanilla, I really liked to know. [this comment contains only description what is vanilla minecraft.jar] 194.137.243.226 EDIT:
 * My error. Looked at wrong hash. 12f6c... is the right one. [this comment contains only description what is vanilla minecraft.jar] 93.106.40.21 21:41, 2 March 2012 (UTC)
 * Doesn't look like an error to me, looks more like some really cool terrain generation. --Nathan2055 23:02, 2 March 2012 (UTC)
 * Is "12f6c" the seed, or is "bug" still the seed? Or is it "md5 12f6c4b1bdcc63f029e3c088a364b8e4"?
 * I can confirm this, but I don't think it's a bug. It just seems like a basin "chunk biome" filled with water.--Gibbl 14:06, 3 March 2012 (UTC)
 * I can confirm this also, and it is definately a bug. A jungle biome for me was cut with stripes of the old swamp biome after the convert. There were also "ghost blocks" in the swamp stripes. To fix just delete (or move) the .mcr backup file and leave the .mca anvil file.
 * This certainly is a bug, and moreover, it's very similar to an older one. Minecraft used to frequently create these "flipped" chunks during terrain generation, which was fixed sometime in Beta, I believe. It appears they're back. --Chromium 02:43, 5 March 2012 (UTC)
 * This has never been fixed as it's never been a bug. Info on it is in the biomes page. It's been proven that it's a purposeful part of the Terrain Generation in the source code. --Moxxy 03:35, 5 March 2012 (UTC)
 * We're not talking about the basin, Moxxy, we're talking about the chunk deformation bug that used to be seen back in Alpha/Beta. An example of it can be found on GetSatisfaction from around that time period. The terrain appears to have sharp, well-defined lines at chunk boundaries, as if the chunks in question have been 'flipped' or somehow misplaced. Another thread on this issue can be found here. I'd ask you not to interject when you don't know the substance of the issue at hand. --Chromium 05:38, 5 March 2012 (UTC)

undefined In 1.2, my Minecraft is generating excessive amounts of floating sand and even floating gravel in the overworld.

Annoyances

undefined Peaceful mobs (manly cows and pigs, but I have noticed it with sheep, chickens and occasionally dogs) can climb vines next to fences. This may be intended behavior, but it makes a major annoyance as you have cows mixing with sheep and escaping their pens in the jungle biome. The only way to fix this is by putting a roof on your animal pens.

a! As of the 1.2 Minecraft update, with a new biome being added, the terrain generation had been modified again. This means beta 1.8 maps are now corrupted, and not just the old pre-beta 1.8 that are messed up. --Gibbl 13:59, 3 March 2012 (UTC)
 * This is a page for things that should be fixed by Devs. Though it may annoy you, this is an inevitability and doesn't belong on this page. --Moxxy 17:53, 4 March 2012 (UTC)
 * He is reporting world corruption after a biome update Moxxy. Just thought you should know.  Gibbl, your tone is a little bit... whiny... no offence.  Report specifics and try to keep it civil.  The Get Satisfaction forum and twitter feeds are the places to tear Mojang's head off if you need to... and we ALL need to once in a while. As to Moxxy's point... unless they rewrote MC's world gen from scratch or put several months of work into a specific world scrubber just for that.. it can't ever be fixed. Sorry.-- Kittani1977
 * OK, I have edited it now to be more formal, and although this can't really be changed, it is still quite annoying, so please don't reduce it to a minor annoyance. --Gibbl 13:59, 3 March 2012 (UTC)

a! There is no way to set the height of Superflat worlds during creation. This makes building underground structures in this world type impossible, and there is no way to stop slimes from spawning everywhere.
 * This is intentional as most people wanted superflat near bedrock so they could build large scale models and such. Unless they make a different gencode for what you were looking for, my suggestion is to use a world editor to set the layers you desire. I think there was actually several tweets from Jeb about it just before they added it but can;t seem to find the link. sorry.-- Kittani1977

a! Worlds in the first Minecraft save format (before McRegion) are no longer recognized by Minecraft and updated to the new format. This causes those worlds to be un-playable. I hope this can be fixed because I have several old worlds that I never bothered converting to McRegion that I would like to re-visit. NZguy 50.135.203.172
 * Not a permanent solution, but in the meantime you can download 12w06a (single-player/client, server, replace the game's minecraft.jar file to switch to the older version) and run the game to convert old worlds to McRegion. Pareidolon 21:44, 5 March 2012 (UTC)

a! Animals get stuck in jungle leaves after player spawn/chunk genereation. They move freely after leaves block removal.

Graphical/Lighting
Bugs

!! If you are very high in the sky(exact Y coordinate is unknown), sky light can pass through solid blocks.
 * I found this above layer 150. Updating the block did not fix the issue for me. I changed to major because when you want an area dark (like a mob spawner), this bug can ruin it. Tested on a 1.2.3 generated world with multiple happenings of the bug. 121.222.226.11 07:29, 6 March 2012 (UTC)

! MC does not repair some lightnig bugs from 12w07a correctly. Water-areas with an floating island above (for example) doesn't show the right shadow. It shows correctly, where the shadows has to be but MC is rerendering that areas very slowly witch causes performance problems. An Backup before 12w07a has not such lightning problems. --Locoloco 18:17, 5 March 2012 (UTC)

! Monsters can actually spawn inside lighting bugs.

! When a layer of cobblestone or stone (presumably any other opaque block) is placed above a layer of ice which was created (in survival or hardcore mode) or placed (in creative mode) with nothing above it to the sky, the ice acts as a light source block but follows brightness levels with the day/night cycle as if the sky remains open above the block. Additional construction can take place above that block, and the light level does not change or vary except with weather and the day/night cycle. --Robert Horning 07:24, 3 March 2012 (UTC)

! Torches spawned in Mines and Villages will show incorrect lighting until updated. May not happen 100% of the time. (1.2.3 actually still does it)
 * This is a bug that has been around at least since 1.0. If you want proof, see this video (auto-linked to correct time). Upgrading to major bug. --Nathan2055 23:11, 2 March 2012 (UTC)

! When pressing the A-key on tiny render distance, it seems to force Minecraft to update the chuck in front of me. - Floedekage 10:17, 4 March 2012 (UTC)

x If a player skin has a head accessory, when sneaking, it will be offset 1 pixel up. Then, when looking down, the head will pass through the front face of it.

x Smooth Lighting still doesn't work on water, there are still cubic shadows on it.

undefined At times a texture will be stretched so that one of the corners is not on the actual block. Stretching may occur to a point far from the block. Observed on versions 1.1, 1.2.2 and 1.2.3
 * This is a problem with DirectX on certain graphics cards, and is nearly impossible to replicate/fix on Jens/Jon/Notch's end.

undefined Sometimes creating a closed in box when you place the final block light will still get through as if the block wasn't placed.

undefined If you surround an upside down slab with other blocks like this, it casts a shadow on the slab in the middle (makes sense for full blocks but not other upside down slabs)
 * I have noticed that if the blocks (upside-down slab) are 2xany its fine but as soon as you place 3xany shadows start to appear. Also torches placed directly under shadows does nothing. - Grey
 * I noticed this with the upside-down stair blocks as well as the upside-down slabs. Makes decorative tunnels/halls impossible, because of the continuous shadow at head-level. Flyindragon1 16:15, 6 March 2012 (UTC)

undefined Players and mobs all seem to face towards f:0 in SMP - Happens in both 1.2.2 and 1.2.3 - Video of this occurring at http://www.youtube.com/watch?v=XXmoiu0gcrw - Lucifer_LLS

undefined There are light sources all over my super flat world. Some are inside blocks I've placed that are not normally light sources, some I've tracked down to be empty spaces, some floating. Additionally (possibly part of the same bug) some grass blocks are shaded while others are not, making an odd pattern. Windows 7 x64 with 64 bit Java.
 * Upgrading to bug. Can anybody reproduce this? --Nathan2055 23:11, 2 March 2012 (UTC)
 * On my server I have places getting shaded where blocks used to be, but currently have no blocks around them. On flat map.
 * could it be something like this: http://imgur.com/a/idLeh#0 its our mob tower, and there are light emitting air/cobblestone blocks all around --bawki, 05.03.2012 TEMP-FIX:
 * install bukkit+worldedit, replace all block types by temporary blocks and convert back afterwards(like: set cobblestone dirt -> set dirt cobblestone) -- bawki
 * I have the same issue as bawki in SSP. 121.222.226.11 07:35, 6 March 2012 (UTC)

undefined When placing a torch on the side of a block such that the air block it occupies is surrounded by blocks (eg:stone) on all sides except below it, said air block will appear un-lit, even though the torch is in it, the torch itself appears lit, and the torch still emits light to the surrounding blocks. Recorded on 1.2.3. -- Cyclone blaze ( user -  talk ) 17:34, 3 March 2012 (UTC) -- confirmed 6.3.2012(bawki)

undefined Rain sound does not activate in 'Extreme Hills' or 'Extreme Hills Edge' biomes

undefined sp Placing and then removing light sources will light the surrounding area but not darken it when the light source is removed. The light level will either remain constant after removal or decrease partially.

undefined Tall grass sometimes displays as partially off of the block it is actually on, appearing to be on multiple blocks at once.
 * Not a bug, it's this way to make tall grass look more "wild": http://twitter.com/#!/jeb_/status/73839858124206080 --Tony311 20:57, 5 March 2012 (UTC)

Annoyances

a! Getting a lot of flicker in MC, seems to happen especially in MCP. No flicker in launcher, possible cause could be the allowance of more RAM by eclipse. 66.68.170.105 20:48, 3 March 2012 (UTC)
 * Found out what could be the problem, MC now has some issues when running in stand-alone mode. When running MC in standalone mode it now appears to update the screen independent of the location of it's container window. This means that in stand-alone mode (quit button is shown) that moving the window will not move minecraft until the user releases the mouse. This also causes a hefty amount of flicker, for some reason... This is also LWJGL Version independent66.68.170.105 21:37, 3 March 2012 (UTC)

a Nether void flickers very rapidly.
 * This is already a confirmed bug for some time now. It occurs when a thunderstorm is active in the Overworld. -- Cyclone blaze ( user -  talk ) 17:34, 3 March 2012 (UTC)

a Upside down stairs when positioned in a square amongst two normal stairs below to make a window frame does not allow light through. This making a normal sized square you can see out of but wont light up your room.
 * "Stair squares" don't let entities through, either. This includes arrows. :/

a There seems to be some lighting errors at chunk boundaries in SMP. Try fx the seed "21", and look at the sea bottom from above. Screenshot: http://thuejk.dk/minecraft1_2_lighting.png

a Heart particles are not appearing when i feed/breed animals. (1.2.3)

Multiplayer-related
Bugs

! Mobs push each other into walls and suffocate.

x We can sometimes see ghost TNT/Sand/Gravel blocks, if many of them have exploded/fallen.

f Sheep on SMP sometimes cannot be sheared or attacked, and clicking on them can activate objects behind them, as if they didn't exist.
 * This bug also randomly occurs with mobs and other player entities. For example in PvP, sometimes you will hit right through a player as if they weren't there.
 * In creative mode, it will destroy the block/thing behind it, which is really annoying.
 * Before, we were just hitting an invincible mob, and not hitting things behind it.

fPutting ":" in the Direct Connect screen without the "s, it will crash the game upon attempting to connect.

! Player data may be randomly lost server-side, causing them to respawn at the default spawn without any items, with their spawn reset, and in the default game mode.

f It is possible for hostile mobs to become invincible, allowing them to hurt players without taking any damage from attacks or catching fire from the sun.

f Server is throwing error on connection:Failed to handle packet: java.lang.ArrayIndexOutOfBoundsException: 16
 * Deleting the player folder from the save folder will sometimes fix the problem.
 * Client side will say: Disconnected By Server, Internal Server Error.
 * Also happens when you die on the server.
 * No player can connect making the server useless.
 * Client must also be restarted after players folder is deleted, other wise the server will have to be restarted again.
 * Removed a 1.2.2 generated world, restarted 1.2.3, players may now login.
 * Removing the player data in the world while the server is running will allow users to login, but no player data is saved. Must be done every time the server is run.
 * This same error happens whenever an op builds above y=140 around the spawn point, which includes (-17, -17) to (17,17). Deleting the player dat files doesn't fix anything. The blocks above 140 have to be deleted, which can be done by opening the file in single player mode and copying the world back to SMP.
 * what about blocks in the spawn point?
 * This problem currently has no fix, will it be fixed in the next update? Is that why it is tagged fixed?

! Server throws severe java.lang.ArrayIndexOutOfBoundsException when "/gamemode playerName (any number above 1)" is used by an OP on the server.

! Some redstone wires do not update after using them after a while.
 * Mainly with torches.
 * Redstone is also causing massive lag spikes, seams to be realated.
 * Lag spikes can be large enough to crash client and sometimes server if large enough restone cicuts are running.
 * There is an entry of this in the redstone section.

! Occasionally, "ghost", unusable items may show in the inventory. If they are moved, they just disappear. This is caused by the client thinking there's an item while the server does not.

! Several sound instances and animations do not play:
 * x Weather smooth transition effect.
 * x Mob/Other Player arrow shooting sounds, snowball/egg/ender pearl/fishing rod throwing sounds.
 * x Chicken egg laying sounds.
 * x Pressure plate, lever, button sounds.
 * x Mob/Other Player stepping sounds.
 * x Other Player mining sounds (the sounds playing before the mining is finished - see Obsidian or Bedrock for examples).
 * x Fishing rod sounds (reeling should not make a sound).
 * x Cave sounds (or at least, they are not synchronized between players).
 * x Slime/Magma Cube jumping animations.
 * x Fishing rod "line".
 * x Fishing rod "line" in held item. It shouldn't appear when the line is casted.
 * x Other Player breaking animations.
 * x Other Player enchantment animations (items/armor).

! Mining takes longer in multiplayer than in singleplayer. This is caused by a click-mining 'fix' that was added in Beta 1.3 and is not needed.

! Knockback and damage screen calculation is often wrong in multiplayer, actually dealing knockback when it shouldn't (like drowning or being on fire).

! Hitting mobs is harder in multiplayer because of lag. It is also much easier for monsters to hit players. Probably a delay before attacking (based on lag) should be added...

! Mobs, especially slimes and magma cubes, tend to bob up and down (being hard to hit) under low ceilings.
 * Slimes will often appear to teleport to the top of an overhang if they get under one and press up against a wall, which is really annoying because they can still hurt the player as though they are still on the ground and are pretty much invincible when they're doing this. In short, slimes can become practically invisible and invincible while maintaining their ability to damage players by pressing up against certain walls.

! Anvil's new per-chunk biome data is not sent in SMP. See here: http://wiki.vg/Pre-release_protocol#Map_Chunk_.280x33.29

f On maps converted by the server, existing minecarts can not be clicked/mounted/destroyed. They can be pushed around. To reproduce:
 * Create map with server 1.1, join, place some rails an a minecart.
 * Convert with server 1.2.3, join, try to enter or destroy minecart. (Make sure you dont have a new minecart in your hands) --Draradech
 * I suspect this is related to the mob feeding/attacking glitch below. --Chromium 19:42, 3 March 2012 (UTC)
 * Explains your 2 sorts of chicken: untouchable are the ones converted from an old map, the others have spawned later. --Draradech
 * Also occurs with minecarts with chests
 * Also occurs with boats.
 * Glitched minecarts can be destroyed with lava. (have not attempted with boats)
 * Ouch! Its much worse than I thought. It has nothing to do with conversion. I assume it affects all entities. How to reproduce fully on 1.2.3:
 * Create a new map, join, place rails and a minecart. It can be ridden and attacked.
 * Logout, Login. Minecart can no longer be ridden or attacked. This is a major problem. --Draradech

This problem can be "fixed" by changing the height of the cart (can be done while still on track) or you can just destroying the cart (arrows still work).

! Under laggy conditions, players, mobs, and other entities may not move for several seconds (players will appear to move on their clients) then move incredibly quickly to their actual position. This can cause attacks (especially arrows) to miss when they should not have or cause mobs to suddenly appear next to players and instantly damage them. Players may also be kicked for moving too quickly.

undefined Player movement is not smoothed enough (the client does this) in fairly or very laggy conditions.
 * This is also the case with mobs.

undefined The skeleton on top of the spider (Spider Jockey) seems to randomly move back and forth on the spider.

undefined Arrows "warp up" when shot on walls. They also disappear and become impossible to collect when shot on ceilings.

undefined Arrow shooting is buggy and sometimes "resets" the charging progress.

undefined Having trouble making dogs change from sitting position.
 * Some mobs appear to be occasionally untouchable; I've only observed this with chickens and dogs. The mob cannot be hit with a sword (although a bow and arrow still works) and cannot be fed wheat to breed them. Dogs cannot be fed, bred with each other or told to sit/stand. It should be noted that this bug has some sort of trigger which I'm not sure of; some chickens can be killed, some can't, and I cannot find the difference between the two. --Chromium 19:12, 3 March 2012 (UTC)

undefined Cats sometimes glitch onto the tops of trees.

undefined SMP drowning pushes the player downwards when taking damage almost as far down as they can swim upwards between receiving damage, making it almost impossible to swim out of bodies of water without an underwater-breathing enchanted helmet.

undefined From what I can tell, mobs still merrily float to the top of enclosures, mostly fences. Once there, they don't seem to be able to escape, but they occasionally flicker up and down. This had apparently been fixed, but it's still happening. Seen on a 1.2.3 vanilla server under minimal load. --Chromium 22:59, 4 March 2012 (UTC)
 * I can confirm this bug occurs on SMP vanilla 1.2.3 however I was unable to recreate the issue in a single player test world. Here is a screen shot of sheep glitching through both dirt and fence blocks.  All of these sheep are enclosed by fences and dirt blocks.SMP_1.2.3_SheepGlitchingThroughBlocks.png --Matthttam 02:04, 7 March 2012 (UTC)

undefined Occasionally, certain dropped blocks and items cant be picked up, regardless of how full the inventory is. This happened while clearing leaves in jungle trees, and it wasn't possible to pick up said leaves, nor saplings. Later, in the same place, this bug did not occur.

Annoyances

a Instead of saying "Outdated Server!" when going on a 1.1 server, it says:" Internal Exception: java.net.SocketException:Connection reset"

a When adding a server, if you come out of full screen mode, it will reset your server name from what you typed in to "Minecraft Server".

a While in a bed, other players in beds will not be visible.

Fixed/Skipped

Items
Bugs

undefined cr When holding a spawn egg and clicking another egg, you get more of the egg you was holding, not switching with the egg you clicked. (Probably also happens with other things with damage values) Minecraft5025 00:35, 7 March 2012 (UTC)

Annoyances

Fixed/Skipped