On my PowerBook (FireWire) and reportedly on a PowerBook G4 (Titanium), it
wreaks havoc if you press the brightness keys.

Basically, it immediately powers off the system, zaps the PRAM, and sets
the date to 1901.

I suspect that this is the case for all Open Firmware 3 PowerBooks, so
simply having abtn disable itself if OF version is 3 would be great.

Here's the difference in dmesg with abtn enabled and disabled:
abtn0 at adb0 addr 7: brightness/volume button

adb0 addr 7: misc. device (remote control?) (31) unsupported


Thanks,
  -- MW