I am certainly sure replacing the old huM models with the newer WoD+ ones would solve this. Looks like an anim fail of sorts, but we can not be entirely sure. Still, I assume replacing models would fix this.
I did the patch for you as you asked me I hope it will fix your problem http://www56.zippyshare.com/v/gEjCTAxV/file.htmlso Now backup your custom patchesremove them from the data folder put this patch patch-C .mpq to the data folder and see if it fixed your problemand in audition I will give a tip (Don't edit the original wow files don't touch it DONT EVEN LOOK AT IT if you edit any of the original file patch .mpq patch-2.mpq patch-3.mpq ... replace them with new ones try downloading wow 335 from torrent or such