Upon it's arrival I went to install it and slowly watched a 15 minute job turn into one that took several hours. Many of you may know that Mac Pro's sometimes have a problem where the internal antennas wires for airport and bluetooth were mislabelled and I apparently have one of those machines. After fiddling for hours with different combinations the best I could come up with was the trackpad sometimes working, sometimes well. Not cool!
I did some research and there are some usb bluetooth options that work for the mac. I picked up an IOGear USB 2.1 bluetooth Micro Adapter, plugged it in and got my Magic Trackpad working within minutes. It can now be used from far away distances too.
If you're in the same boat I'd suggest you forego the bother of the Apple bluetooth card and just get one of those guys. I'm using Snow Leopard and it's working great. You don't even have to install anything, it just works right away.
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