Comment 15 for bug 548992

I too got broken wireless upon upgrade to lucid. It was an USB dongle using driver rt73usb. Simptoms were the same deauthenticating barrage of messages, and mangled essid.

Following the clue of a previous reporter, I saw that I too had network-manager installed, albeit I use wicd. Killing the process (sudo service network-manager stop) didn't work. Uninstalling the package, however, did it even without rebooting.