Blocks changed

Trapdoors

Can now be placed on the top half of blocks

0x4 is a bit that determines whether or not the trapdoor is swung open. 0 for closed (on the ground), 1 for open (against its connecting wall). 0x8 is a bit that determines whether the trapdoor is on the bottom or top of the block. The remaining two bits describe which wall the trapdoor is attached to:

• 0x0: Attached to the south wall
• 0x1: Attached to the north wall
• 0x2: Attached to the east wall
• 0x3: Attached to the west wall

Stairs

Now connect to other stairs to form corner stairs https://twitter.com/jeb_/status/237491122828632065

Repeater

Can now be latched by having another repeater entering it's side. This doesn't look like it changes data values, however might need to check for rotation control.

New blocks added

137     89  Command Block T
138     8A  Beacon T
139     8B  Cobblestone Wall B D
140     8C  Flower Pot D I
141     8D  Carrots D
142     8E  Potatoes D
143     8F  Wooden Button D
144     90  Head D T I
145     91  Anvil D

• D = Requires Data
• I = inventory item different
• B = Damage Field
• T = Tile Entity

Data values

Cobblestone Walls

Value   Description
0   Cobblestone
1   Moss Stone

Flower Pots

Value   Description
0   empty
1   Rose
2   Dandelion
3   Oak Sapling
4   Spruce Sapling
5   Birch Sapling
6   Jungle Tree Sapling
7   Red Mushroom
8   Brown Mushroom
9   Cactus
10  Dead Bush
11  Fern

Heads

Note: Only part of the information for this block is in the data value, the rest in the associated Tile Entity. See Tile Entity Format for details.

Data values determine the block placement:

• 0x1: On the floor (rotation is stored in the tile entity)
• 0x2: On a wall, facing north
• 0x3: On a wall, facing south
• 0x4: On a wall, facing east
• 0x5: On a wall, facing west

The skull types (for the Item and for the Tile Entity) are:

Value   Description
0   Skeleton
1   Wither Skeleton
2   Zombie
3   Human
4   Creeper

Anvil

0x1 is the bit that determines whether the anvil is orientated in a north-south (0) or a west-east (1) direction. 0x4 and 0x8 are bits which determine whether the the anvil is a regular (0x4 & 0x8 = 0), a slightly damaged (0x4 = 1) or a very damaged (0x8 = 1) one.

Carrots & Potatoes

Value
0, 1
2, 3
4, 5, 6
7

Handy page for future note:
http://www.minecraftwiki.net/wiki/Chunk_format#Tile_Entity_Format

Released version 0.6 with support for 1.4.5