Macppc G3 Powerbook - Install Fails

[Roy Morris]

I have a buddy over who wants to put OpenBSD 3.8 on his macppc G3 
powerbook (bronze keyboard) we burn tested the boot cd on a G4 Powerbook 
and it does boot fine. When booting on the G3 none of the normal 
installation methods work, it just seems to go right
by the cd and boot into the mac os. Any ideas what we might be doing wrong?
Thanks!
Rm