Papercut just adds authentication to AirPrint when using a CUPS print queue. On a Mac print server it also shares the printers giving the correct information via mDNS/Bonjore/zeroconf for it to appear on a iOS device.
I have set up for limited testing purposes (in preparation for the web app papercut has to support iPhone and iPod Touch) a number of printer queues on a Linux server. I then made them show up on iOS devices using avahi and some XML. Once everything is working I installed papercut as a secondary server on the Linux box. Make sure the URI for the devices now start with papercut: before the normal URI (forgot to do this first and was wondering why it was not working!). After doing a test print you need to make the guest user an unauthenticated user in the PaperCut web interface.