When you use MCEdit to create a Villager Zombie Pigman, half his head is missing.
Even though you can't create a Villager Zombie Pigman without a 3rd party tool (in this case MCEdit) it's very annoying. I wanted to create something like a cursed villager in my adventure map but instead of giving me half pigman - half villager (or villager zombie) it just created a zombie pigman with only half a head.
Maybe there aren't many people that are trying to make villager zombie pigmans but it would be nice if this could be fixed.
This can not be obtained without regular means, and as such is not a bug if it doesn't work correctly.