TNT is Backwards

What I expected to happen was...:
The texture for TNT would appear correctly.

What actually happened was...:
The letters were backwards.

Steps to Reproduce:
1. Open Minecraft (this step is important )
2. Place TNT

The item in my inventory was normal, however. This bug probably doesn't just affect TNT, although it is hard to tell, since most other textures flip without having a noticeable effect.