 <p>It's pretty late, but I got around a similar problem using masking</p> <p><a href="http://www.aurelienribon.com/blog/2011/07/box2d-tutorial-collision-filtering/" rel="nofollow">http://www.aurelienribon.com/blog/2011/07/box2d-tutorial-collision-filtering/</a></p> <p>cheers.</p>