I don't mean to be a pain, but this really is driving me crazy... Here are some screenshots to show you what I mean - the last two were taken while both the characters were moving forward - and they pass right through one another!
http://vulcan.spaceports.com/~lethargy/collision.html

Thanks for any help,
Keith

P.S. None of the visuals are mine, btw - the models are from the old Quake II Gauntlet project - I've just been using them as dummies so I can get the programming done before creating my own models.