To clear this up.
UO:Third Dawn introduced the UO 3D Client which uses the *.grn (RAD Granny FIle Format) for all Characters, Monsters, Animals and Clothes+Weapons.
AoS continues this Client and also UO:Gold and Aniversary Edition. Currently EA killed the whole 3D Client and don't distribute this models anymore with thier current Setup.
We wrote a decoder for this granny format and use this models in
Main Page - Iris . There is also an old Grannyviewer at berlios from our abbadoned iris1 project.