Moving Origin of a Body

I have a entity (mesh of a creature), and I want to attach a Body to it. The body itself is a sphere primative, and is created at the base of the creature (between the legs). How would I position the sphere body at the head instead? I've tried re-positioning (both setPosition and translate) the scene node after creating the physBody but that doesn't change a thing.

Any help would be great.

I'd say just make a compound collision out of the body and the head part, position the head and body relative to each other properly, then stuff into a compound collision, then give to your class...