gtk apps crash X in 8.04

[Dexter Filmore]

Showstopper: when I enter text in a gtk app (tested with firefox-2 and 
OpenOffice Writer) sooner or later X will freeze. Mouse pointer still works, 
machine is running, I can even ssh in and shutdown cleanly, even ssh -X and 
run X apps remotely, but the local display stays dead until the machine 
reboots, can't even switch to ttys.

This renders the system unusable to me.

Anyone else got this? I already filed a bug report, no answer so far. Friend 
of mine experienced this, too tho he could switch to tty and restart X/kdm.

He has an NVidia GF 6800 AGP, I got an X800XT (R420) AGP, both nForce 2 mobos.