System Crashes

I’ve got a seemingly random system crash. Based on the logs, it appears that the X server is freezing. This crash is generally associated with web browsing, but it requires active user user of the web browser (not just watching a video, for example). The event that triggers the crash is not necessarily associated with the browser (last time it was simply clicking on the application menu). It seems that the network manager gives the same message in the log files every time the crash happens (see below for the logs).
After crashing, I’ve tried to kill the X server (ctrl+alt+backspace), but that causes the screen to switch between black and just showing the cursor. It settles on just showing the cursor, however at that point even the mouse does not work. Here are the relevant sections of the logs:
If you need anything else, please ask. Thanks!

A few essential details: I’m running 11.1 (32-bit) with KDE4.1 on an HP Compaq nc6400 (intel chipset, intel T7200 processor).

Have a read of these two links may provide further detail, but appears
disabling Xinerama in the xorg.conf file may fix it…

Cheers Malcolm °¿° (Linux Counter #276890)
openSUSE 11.2 Milestone 5 (i586) Kernel 2.6.31-rc5-git3-2-desktop
up 6:11, 2 users, load average: 0.16, 0.10, 0.02
ASUS eeePC 1000HE ATOM N280 1.66GHz | GPU Mobile 945GM/GMS/GME

Thanks for those links. Xinerama was already disabled in my system, but (as per the links), disabling compositing fixed it.