lprng to cups

A new machine has CUPS and some old ones have LPRNG; how do we print from the old PCs to the printers attached to the CUPS m/cs? Bearing in mind the old PCs work just fine, so replacing LPRNG with CUPS isn't an option. What I was looking for was some kind of LPR-like client. -- Simon Dales, Software Consultant "The impossible is easy"