>> 	Hey, I just finished a CD I was trying to boot my iMac DV with,
>> and upon trying to load the ofwboot.elf image, it reports ``unrecognized
>> client program format.''  Is this a known, obvious stupid thing I'm doing?

AFAIK, OF-3.x boots from HFS CD, not cd9660.
You can make bootable CD with mkhybrid -hfs -part.

(and type ``boot cd:,ofwboot.elf'' from OF to boot.)