make sure to disable WEP in the selected configuration before starting netstumbler or else NS will try to use that WEP key to connect to any networks it finds, which will yield the results you're getting. however, even if that's not the case, if you're stumbling a network you can't be sure of what you're getting into... the strongest signal access points that i've ever found, at a hospital, have no WEP, amazing signal strength from even a block away but yet i get no IP# and there is no traffic visible to the usual ethereal sniff. your best bet is to make sure your setup is working in a controlled environment before trying it on the road...