well i am not sure of the exact configuration on a 4500 but i have 2 e3500s and 2 rs/6000s and 1 ultra5 hooked up to a dummy terminal.
i got the KVM from blackbox model # SE-RS-8-HFC.
on the 3500 its not a db25 (no i dnot have a grafix card in it either) but it is a propriatary port.
if you call up blackbox (
www.blackbox.com) they sell the cables needed and are more then willing to help you out.
They come in all lengths.
Just tell them exactly what you have and what you are trying to do and they will hook you up.
also i know the console port on the e3500 is automatic, and no configuration is needed.
now if your useing a video card your ovestly going to need that proper cable as it is also a propriatary sun port. again blackbox is the hook up and can get you anything or even make you any kinda of cable you need.
just call em. its free and you will find it well worth your time.