using the same set up as you with an old style ps2 KVM. For newer pc's I am using a USB to PS2/Mouse adapter. The cheep ones work for most things but can not action the (backslash) key. As you can see the one I am using can not. I am told the 'better' ones can.

I am ordering a docking station for my new laptop and have noticed that it comes complete with 2xPS2 connectors for mouse and keyboard! So, at least the PC makers are still putting the connections there!