After I had several random kernel crashes, I have tried to figure out what was the cause. It seems to be caused by nvtv. The following triggers most of the time, but not always, a crash:
1. run nvtv and click on "TV on"
2. run gdmflexiserver, which opens a gdm login on a new VT
3. the kernel crashes during xfree86 start up.
I'm using the following versions:
I'm using a "nVidia Corporation NV11 [GeForce2 MX/MX 400] (rev b2)" card with tv out. X is configured with two X screens but not twinview or xinerama.