A couple of weeks ago, I bought some extension cables to allow me to play SOCOM 3 while sitting on the couch instead of sitting on the floor. The extension cable for the controller worked perfectly. The problem I had was with the extension cable for the headset.
The headset connects to the PS2 through the USB port. I bought a standard USB 2.0 extension cable. When I connected the cable, the headset wasn't recognized by SOCOM 3. I think that the headset is just using USB 1.1. I would assume that you could use a USB 2.0 cable for USB 1.1 devices.