Comment 10 for bug 309311

Well, let's try another way.
Boot Ubuntu in recovery mode (2.6.24-22), when prompted, go to a root shell.
You will need to edit /etd/modules and disabling madwifi from boot; the simplest editor is nano, so give "nano /etc/modules", find all occurrences with "madwifi" inside and comment them by adding a # at the beginning of the line; save (Ctrl + O - Enter) and exit (Ctrl + X); then reboot in "normal" mode; it should not crash. If you want some details while booting, when usplash (the black and orange screen with the progress bar) appears, press Ctrl + Alt + F1 and you'll see boot details;
When booted, follow the instructions you find at
http://ubuntuforums.org/showpost.php?p=5703118&postcount=3
(download files before starting editing or you won't have an active internet connection =) )
I don't know if you have found this guide before, and if you download the updated version of madwifi-hal every time, but it seems to work; sorry if I can't help more :(