Comment 6 for bug 577997

I've managed to reproduce the same bug on a different PC, running nvidia 96 driver and also having a dual display. The only difference is that I didn't get a stack trace in Xorg.0.log when I killed X. The trigger in all cases has been moving the mouse cursor between the screens (going from one screen to the other).
AndyB - can you try to reproduce the issue by either moving the mouse pointer quickly between your screens, or by dragging a window between the two screens? If what I'm seeing is the same bug as what you have, you should have a crash independent of the login switcher...
By the way, it seems it's not connected to the kernel update - I tested on systems before and after the update and I reproduced the bug.

Regards.