There is this great bullet rag doll example that is entirely render-engine independent, strictly Bullet goodness by Marten Svanfeldt. I was able to hack it around and get it running with Irrlicht:
The visual sizes are a bit off because it's using spheres, not capsules. That and it would seem bullet body positions are actually pivot points, not centers of the body...Not sure how to translate a sphere locally...kinda wanna know that now - anyone? Anyways, the collisions are there. Right now it uses bounding capsules, which I read are unoptimized in Bullet physics so I'll probably change those to a mixture of spheres and boxes when i implement it personally into my game.
In anycase, here's a simple bullet irrlicht rag doll demo + source.
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