My skin, which was the original ''steve'', was changed into a completely brown-headed blue armed skin, and the head was incomplete, and i was using a texture pak that i created and did NOT change the default skin. the skin could be a cool adition though, and it just happened. no special hack, and no change to the skin. i tested the head and skin without the texture pak, and it was fine. it seems that whenever i load a texture pak, that happens no matter the t. pak
Actually, issue with your resource pack, not a bug.