http://www.bulletphysics.com/

Please consider replacing ODE with Bullet. Bullet also is an open source physics engine (zlib license) but it is more actively developed and has more features.

ODE is kind of lacking because it only fully supports boxes and spheres as collision shapes (the rest of the ODE shapes like cylinders aren´t complete) and it isn´t really stable enough (explosions happen too often and too easily!).