Java Edition 1.6.3

1.6.3 is the first and only pre-release for Java Edition 1.6.4. It was released to provide a fix to allow structures to be saved with the world file.

1.6.3 was reuploaded on September 17, 2013.

Fixes
2 bugs fixed
 * – Structures (witch huts, nether fortresses etc.) do not get saved with the world file.
 * In order for current structures (witch huts, nether fortresses, etc.) to be saved to the world file, the player must load the appropriate chunks within the game manually. The game will not automatically scan worlds and update structure data globally. After this is completed, structures will be compatible in all snapshots starting with snapshot 13w37b.
 * Fixed a handshake exploit.