[ODE] Disabling geometries

[Matthew Reid]

Hi.
I'm having some problems with disabling geometries with dGeomDisable(). When 
I disable a geometry, I find that it still generates contacts. The state of 
the geometry in the collision call back is usually shown as enabled, 
although it sometimes shows up as being disabled. I've tested this with 
capsules, spheres, and boxes against rays and trimesh.

I have two questions - what's causing the geometry to be automatically 
re-enabled? And how is it possible for a disabled geometry to generate 
contacts?

Thanks,
Matthew