Bug#405201: more info
I had the same problem today (again). This was not a debian or an xserver
problem (for me ?). My X server was crashing when using kde and running any
opengl app or xawtv. When starting a new X server with no wm:
X :0 & (sleep 5s ; DISPLAY=:0 xterm)
and running the same app in the xterm there was no problem.
It seems that this is caused by new X packages that override the nvidia glx
libraries. To solve the problem just reinstall the nvidia driver.
When reinstalling the nvidia driver, an error message is displayed that
proves (?) this:
ERROR: File '/usr/lib/xorg/modules/extensions/libglx.so' is not a symbolic
Hope this helps...