Not sure if it's just me but I find that the only heads that display properly on my 1.8/1.8.1 client are Slimes, Zombies, Creepers, and Skeles... all others including player heads are broke. Is this something that can be fixed in the future?
It's a spigot issue with the current version emc (and other servers) are running on... When emc goes to the newer spigot version it should be fixed.