IPP printer problem

[Ronald]

I have used the Samsung install disk for Linux for a networked CLP-500 colour laser. under FC1. Everything goes swimmingly:
* The Driver is installed
* CUPS is up and running
* The printer can be pinged at 192.168.0.5 and is using port 9100
* The printer works fine from a W2K box on the same subnet
* All the defaults look ok
* Printing a test page from Control Centre works fine

...except the job just sits on the queue, and there is no sign that CUPS is talking to it.  When you you right-mouse-click and ask for "Printer IPP Report" it says the printer is busy and that it will retry (which goes on forever).

Any advice much appreciated.

Ronald