Put wlan card into monitor mode.
Then run "airodump-ng --channel 6 [name of monitor mode interface, usually wlan0 or mon0]" as root. If you want to actually record the captured stuff, use the -w flag to give the main name of the file, and --output-format to specify what format to save the captured packets in.

"airodump-ng --help" is your friend. Also the aircrack-ng wiki.

For everyone else: My next plan with this package is adding a bugtracker field to the debian/control file (or wherever it's supposed to go), and then seeing if I can push it to extras-testing. Once there's a version down in -testing, I won't have to feel guilty about breaking the -devel version (well, before I didn't have to either, but it was easier to keep it working than explain to everyone how to get older versions of packages from the repository), and that means I can start experimenting with automatically installing to /opt/maemo/... and putting symlinks in the default path (/usr/[s]bin).