When using the Default Texture pack all mobs and heads have the words Missing Texture on this.

What I expected to happen was...:
the mobs and heads would appear normaly like they always do when using the default texture pack

What actually happened was...:
All mobs and heads appeared white and has the word Missing Texture on it. For some reason the default texture pack is not applying to any of the mobs or heads.

Steps to Reproduce:
1. By spawning or placing a mob or head
2. They appear like this when using the default texture pack