I have a dealextreme alfa knockoff, and had the same issue you do. I may forget some details here, but basically I downloaded a newer version of iw and got it to work. I didn't want to replace the version backtrack has since I was unsure if that would break anything, so I just grabbed iw (iw-0.9.9 in my case) out of the downloaded directory and used it just for this.
A simple script set to run at startup worked for me:
Check dmesg to verify things went smoothly. It may be against the law to do this depending on where you are, etc.
/[insert path to new iw]/iw reg set BO