File: contrib/dCylinder/dCylinder.cpp (current CVS version) Function: dGeomCylinderSetParams dUASSERT (g && dGeomGetClass(g) == dCCylinderClass,"argument not a ccylinder"); The assert triggers, because obviously dCylinder is NOT ccylinder. Btw, is it the right way to report bugs - posting them to the list? Hopefully someone who can fix them notices them here. - michal