Ok, I got an IOGear GCS14 4 port PS/2 KVM switch the other day and I've been having problems with the mouse. It's at least working but the cursor is a little jerky when you move it around the screen ...

I've got a USB mouse (MS) that came with a USB to PS/2 converter. It works fine hooked up to a PS/2 port. I run it through a KVM switch that is PS/2 and not USB so this is necessary. One of the boxen ...