I wrote in January about some strange G4 PowerBook power supply behaviour. Unfortunately, the problem re-appeared at the weekend. Unlike last time, when rebooting the PowerBook fixed the problem, I haven't been able to get it working again, and I'm running out of ideas. I've tried resetting the power management unit, and I've run through Apple's troubleshooting algorithm. Hopefully I just need a new adapter. I'll take it in for repairs tomorrow.