install: "sorry, no cd/dvd drive was found on your computer!"

[Jamie McClelland]

Hi all --

I have an iMac I purchased new last Spring (700 mghz, version 2.1). The 
only modification I've made is to increase the amount of RAM (to 640 MB).

I dowloaded Yellow Dog 2.3, burned the ISO to a disk and booted from the 
CD. Yaboot comes up without a hitch.

Then, I choose install-gui. First - I don't get the gui install, I get 
the text install. Not a big deal. However, when I get to the part about 
choosing the install medium (which only gives one option - DVD/CD), I 
get the error message "Sorry, no CD/DVD drive was found in your computer."

I've tried every install option, including default and custom, the 2.2 
kernel, text and gui mode and always get the same message.

Any ideas??

Many thanks,
Jamie