Comment 8 for bug 1035590

Could there have been changes to the wext interface for the ipw2200 driver in the new kernel revision? NM fallsback to wext for drivers such as ipw2200 (and ipw2100) which have an incomplete/broken nl80211 implementation.

I'm just about convinced it's not an issue in NetworkManager since it hasn't changed recently and we released with 0.9.4.0-0ubuntu3 which includes the patch to fallback to wext; which reportedly works properly at least on 3.2.0-23 and 3.2.0-27. If necessary and the nl80211 code was fixed, we can drop the patch, but there are some things to consider.

See https://bugs.launchpad.net/ubuntu/+source/linux/+bug/973241 for details.

See also:
http://article.gmane.org/gmane.linux.kernel.wireless.general/88613
https://bugzilla.kernel.org/show_bug.cgi?id=43049

Basically; including the device capability (encryption) patch will make the NM patch not fallback, but then the signal levels will be missing, because those are missing from nl80211 as well.