How can I use my 23" HD cinema display(ADC) with my PC

Hi
I have had to move my workspace into a very small room so want to use one monitor, keyboard and mouse with four computers, via a KVM switcher to save space. The monitor in question is the Apple 23" HD Cinema Display (ADC), which I paid a fortune for about five years ago, but still looks like new! The computers are my G4 (ADC & DVI)and three windows PC's running XP and Vista, also DVI output. IOGEAR make a switcher that supports four computers running a mix of OSX and Win XP and Vista. If my display was the new DVI screen then it would be simple, but I cannot work out how to connect my screen with its ADC only connector into the KVM. Does anyone know or could anyone recommend a solution?
Mactavish