Booting an iBook G4 into Linux from an ext3 USB hard drive partition

This post needs to be edited, but here's the dirty part:

mkofboot -v -b/dev/sda1 -o usb
(apple)+(option)+O+F
> boot usb0/disk@1:yaboot
> dev usb0 ls
> boot usb0/disk@1:2,\boot\yaboot
or > boot usb0/disk@1:2,\\:tbxi
or > boot usb0/disk@1:2,yaboot
> dev / ls
> devalias
yaboot: hd:3,/vmlinux root=/dev/hda3 ro