Knoppix on Laptop w/external CD

I am successfully using Knoppix 3.9 on laptop hard drives to display Photographs. The photos are loaded into a different partition on the hard drive, and Knoppix loads the image viewer (fbi) at boot and displays the images.

Changing photos requires unmounting and remounting the drive rw, uploading photos from a USB drive of some kind, and then reboting. The setup above works great for me, but I want people to be able to use this setup as an appliance. Specifically I'd like them to be able to put their photos on a CD and just pop them into the CD drive and power on the machine.

This is where the problem lies. The laptop (a Dell CPi in this case) recognizes the hard disk as a CD drive due to booting with ISOLINUX. When I connect an external CD drive the system sees it as a "floppy/CD drive", and does not recognize the CD in the drive. My guess is that the laptop thinks the CD drive is a floppy since it "already" has a CD (actually the hard drive).

Has anyone got a solution where I can read CDs from the CD drive while running KNOPPIX from the HD?