PB Screen Issue

[AngeredTree]

I have my Powerbook's screen set to turn off automatically after 5 minutes or so, but sometimes when i "wake" it back up (It's not sleeping of course) the login window pops up, and I login normally, but nothing happens, the screen stays dark. When I adjust the brightness settings, the screen gets "lighter" but still no image appears. When I try to push any button, i get the alert beep, and I can't get the login window to reappear. iTunes still plays in the background, and everything seems normal, except that I cant see anything on my screen! I end up having to restart.

(10.3.5 April 04 PB 15in, only iTunes and Adium running)

Very annoying...anyone have any tips or similar experiences?

Thanks