How do you make cloths collide with stuff? I tried making a deflector, I tried freeing the simulation frames in the cache of the cloth, but it doesn’t work. The same happens to me with soft bodies. I posted this before, and got responses, but that’s not working here. It falls through. Helpy?
what version do you use?
There are new svn-versions without sometimes game-engine and one of the last(or still the last) with no cloth-colliding - dont know the reason, could be the engine uses some other routines(bullet-?) to calc. it.
It it is the standard 2.48a version from blender.org, collision should work without problems,
if - you did not mix it with any old installs- and you for shure have to set other objects to collision too and all have to be in the same level(screen?, virtual overlay screen … how to call it?)
I have no idea what you mean by overlay, and I’m using a file which I have worked on across the versions. But that is irrelevant, because even in a new scene, cloths don’t collide. I think i noticed this a long time ago, but I only care now.
There should be a little slider in the cloth collision tab that allows you to change the collision quality. if you bring this up to about a five, the cloth should collide with the object.
What?! It’s not a slider 
Seriously, though, this doesn’t work.
I had the same problem with an svn build I made…
It seems it was a bug.
http://lists.blender.org/pipermail/bf-blender-cvs/2008-December/017110.html
It’s fixed now.