I'm sorry to say that the BCM cards are not really well supported within the BT community. I have Broadcom cards on most of my laptops, and I had to buy a USB card to allow myself to connect with a wireless connection.
Some of the BCM4312's work, others don't. The revision that you have is the one that I believe doesn't allow you to use the card. Go ahead and look at this for a quick overview of what cards work with what. Wireless Drivers | BackTrack Linux
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