Denon AVR-4800 Optical Input problem

Hi,
I have a Denon AVR-4800 to which I have connected a pair of Sony ES series CD decks. I'm using the optical connections and have the AVR-4800 inputs set to "Optical1" and "Optical2". The CD decks play fine but I can't figure out why there is no output at the analog Tape1 and Tape2/Mon outputs. In order to record from either CD deck I have to connect the RCA cables between the 4800 and the CD decks. I assumed that I would be able to record from a CD using the optical inputs since the optical/digital sigal is converted to anaolg at some point. Does the 4800 not provide an analog output from optical input sources? Or have I missed something in the setup?
Thanks,
Jeff