I'm having the same problem with my Asus eee netbook. It looks like the brcm80211 module is not installed with the 18.104.22.168 kernel in BT5r1. You can try 'apt-get install linux-image-2.6.38' and booting to that kernel, this provides the brcm80211 module and was the default kernel for BT5. I'm going to attempt this myself this week, maybe even see if the module can be loaded in the newer kernel. I don't use the built in wireless for injection, it's range sucks, I have a alfa usb adapter for that. I just want it to work.