i've got a g3/800 ibook that has developed an issue w/ sleeping. basically: - i close the lid, it doesn't go to sleep - i open the lid, and sometimes it then goes to sleep i've seen some others over at the apple discussion forums w/ the same issue, but nothing suggested there resolved the issue. i actually dropped $50 on apple tech support, where we did a number of things (including resetting open firmware and resetting the PMU), but the issue remains. he suggested i send the unit in for repair. what i don't know is what hardware trick is used to tell the PMU that the lid is being closed. when functioning properly, my ibook goes to sleep just before the lid is latched closed, leading me to believe there's some kind of sensor around the hinge area. does anyone know for sure?