Here is a free high-res skeleton model I found (1.2M polys):
(LINKS REMOVED)
I had a small network hickup while it was uploading, so let me know if the file is corrupt, and I'll try uploading it again.
Oh, I forgot to mention, there were too many polys to convert to .3ds, so I converted it to .obj format (Max exported the .mtl file along with the .obj). I don't know if jPCT is able to load .mtl material libraries, but if not, this skeleton model only has one material - light grey (bone color), so you could just apply a grey texture to the model after loading (there are no UV maps for this model - texturing is done entirely with polygons). I'm searching for even higher-poly models than this one, and I'll let you know if I find something.
-EDIT
No luck finding anything for free that has more than around 1 million polys.