I fear there is no nice solution for that problem.
Do you know the Replace Bones Matrices in MED? At least this let the bones react normal to the move tools...
3ds contains the mesh only as far I tested this all.
You can export the bones as ASCII, but I don't know whether you can import this to blender. Maybe, you can do it via Milkshape3D.
But, in the end its probably less less hassle to build and rig the bones in blender anew.