A1242 Keyboard Problem

Just purchased an Apple A1242 keyboard (the wired type without a numeric keypad) off ebay. I've plugged it into my late 2009 13in Macbook and I keep getting a message saying "A USB device needs more power". If I look in the system info under USB, I can see it is recognizing the keyboard as a hub (presumably because of the 2 usb ports on the keyboard) however it is failing to even recognize the keyboard itself. I know Apple USB ports are supposed to configure themselves power wise but its not even overloading either USB port. (500mA available, using 174mA)

Not sure what to do? It doesn't work on a powered hub either. I plugged it into my GF's Asus laptop and it worked fine so I think the keyboard itself is ok. It's annoying and I don't really want to go back to using the blutooth keyboard I have as it hangs a lot and from what I've read, it's because the Macbook blutooth is ****. I'm using OSX Lion 10.7.3 if that helps.

Cheers

Aaron