I have the same problem on a G3 Wallstreet II Powerbook. Interestingly, when I test it out using showkey, most of the time nothing happens, but occasionally one press of the power button will cause showkey to display 0x74, and then to display 0x74 about 100 times over, and then, after a short pause, to display 0x74 about 100 times over again, and again and again, until another key is pressed. After that another press of the power key seems to do nothing.
-- Power buttons on PowerBook G4 1.5Ghz does nothing https://launchpad.net/bugs/55336 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs