[lug] Removing power cord locks up Suse 9.3

This is my first post, so if it belongs is another group, let me know.
I have searched high and low for a solution to this problem before
posting, but found nothing.

I installed Suse 9.3 on my HP zt1290 laptop without problem. I got
everything working fine but if I unplug the power cord, the system
locks up indefinitely.
I have to shutdown the system using the power button and restart to get
everything back up and running.

I have two hard drives for this computer, windows XP and Linux, and I
can plug/unplug when running windows without any problems, so I don't
think it's technically hardware. Perhaps it's the way Linux
interacts with the hardware? I'm not sure.

Has anybody heard of this problem?

I'm new to linux and any help would be greatly appreciated.

Eric