So from
12w32 to minecraft 1.4.2 pre realese i still have this issue.
almost all the new textures in minecraft 1.4 are purple. I have even looked in the
minecraft.jar file, and all the textures are there. But in the game the textures like
The command block, the anvil, flower pots and so on, are purple. But the new mobs like the witches
and the bats are normal.

EDIT: Im not using a Texture Pack if anyone wants to know. Its default minecraft