Milkshape question - How do I join two animated meshes?

I have a animated horse mesh and a animated rider mesh .. how do I join them, while keeping both skeletons?

For what purpose? They can't share a surface unless they also share a texture.

Unless you have some specific purpose - Dont joint the rider mesh to the horse mesh - it would take a lot of work to join the two skeletons together with their animation intact !
Instead parent the rider to the horse. This will make it much easier to work on the animations seperately and to allow your rider to fall off or dismount etc.

yes, thanks smiff, the answer is don't, let blitz do the work. Hard bit will be aligning the meshes first.