Java Edition 12w03a

12w03a is the first snapshot released for 1.2.1.

Additions

 * Added jungle biome (requires new chunks)
 * Added jungle wood
 * Added jungle leaves

Changes

 * Ladders regained their collision box
 * Vines are climbable if you push into a solid block while next to them
 * Updated language files
 * Dispensers dispensing spawn eggs will place Mobs instead of simply dispensing the eggs
 * Spawn eggs are now stackable
 * Zombies have new path-finding AI
 * Wolves have new AI and can be bred by using chicken (raw or cooked), porkchops (raw or cooked), steak/beef, and rotten flesh when tamed.