sudo apt-get install sg3-utils (only needed the first time)
ls /dev (to check whether sr0 or sr1, usually it's sr0 unless you had already other USB drives connected)
sg_raw /dev/sr0 EA 00 00 00 00 00 01
Macs don't have a BIOS. They have something called Open Firmware instead. So the BIOS password is called Open Firmware password. You boot into Open Firmware by pressing the command (=apple), option, O and F keys simultaneously during system boot. To set the password type password To enable the protection type setenv security-mode full An then reboot by typing reset-all Apart from the full security mode you can also set "none" (= don't ask password during boot) and "command" (=gives you only limited access to Open Firmware without the password.
I am trying to get Ubuntu 5.04 or Debian 3.1 running on the original PB G3 (aka Kanga aka 3500). The only problem: the screen is blank after the inital reboot after the installation. Nothing at all (Ubuntu) or only an inverted penguin (Debian). The boot process continues only if one copies over the ramdisk image from the /boot folder onto the HFS partition and specifies it as boot argument. Might it be that the root=/dev/hda8 (in my case the root partition is hda8) is somehow not recognized?