I'm using GNOME with a 10-minute Screen Blank and automatic Screen Lock disabled. Sometimes, it's not enough to move the mouse to wake up the display. But I can Ctrl-Alt-F1, giving the gdm login screen, and when I log in, I'm back to my original session (not a new session). It happens occasionally, but usually moving the mouse is enough to wake up the display. AFAIK I'm not doing anything differently when it happens, so I'm pretty sure it's a bug. Anyone know?