I thought it might be worth giving this a shot. I attempted to connect a Logitec MK300 wireless mouse and keyboard (Transmitter has one USB connector) using gender changers. I tried connecting it through a Belkin/Omniview 4 port ps2 KVM.
It doesn't work. The USB to PS2 adapter is really designed to go the other way, i.e. to take a USB signal from a workstation and split it out to a wired keyboard and mouse. It doesn't work when you attempt to combine two ps2 connections from a workstation into a single usb connection (the transmitter which drives the wireless keyboard and mouse).
It would be nice if there were a solution out there since many of us would like to keep our PS2 style KVMs alive.