Real-Time Physics Simulation Forum

Although work in progress, there is upcoming support for Physics specification in the next COLLADA XML schema 1.4.0. The Collada Maya exporter has early supports for this:

http://colladamaya.sourceforge.net/

Although not up-to-date, there is a document about Collada Physics:
http://www.feelingsoftware.com/Physics/ ... eNotes.doc

Expect 3DS, Softimage, Blender support too.