xbox 360 controller not working

Online I've found guides to use the Xbox 360 controller on Mac. The driver is compatible with OS X Tiger but the controller doesn't show up under the Xbox 360 Controllers preference pane. I have the controller plugged into the USB on the back on the computer (the keyboard usb says that it doesn't have enough power, no surprise.) and even after restarting the computer it doesn't show up. I KNOW this controller works because I can use it on both an actual Xbox 360 and on a notebook PC. Any idea?