I had a feeling before I looked at this thread that I'd be able to help you. And I can! I had a Dell 1395 Minicard -> Broadcom 4312 which I used to use ndiswrapper for, but Broadcom has released an official driver for it so you can just use that. I wrote a tutorial for it if you want: http://www.hydronitrogen.com/409/bro...-on-slackware/
The tutorial says on slackware but it should work fine elsewhere as well. This should work fine also because I believe Backtrack is a slackware derivative. Try it out and let me know how it goes.