camorri: Thanks for that link! That program will certainly be useful in future old machine installs I plan to do... however, it did not work in this case, because the CD-ROM is connected via a SCSI controller (remember when everybody was gay for SCSI?) and SBM couldn't detect it.
thisbl3: I forgot to mention that I've used that before. It doesn't work on the machine I'm testing it on: it just hangs up. We're talking a Pentium I here, with a SCSI hard drive and CD-ROM... I don't know if that's the issue or not...
That being said, I did manage to "trick" the SCSISelect Utility installed on the machine into thinking the BIOS was set to boot the CD-ROM first (even though the BIOS has no idea there's a CD-ROM connected at all).
So I was able to boot the CD!
But now I'm getting a "Knoppix filesystem not found" message... Time to go forum searching...