Comment 5 for bug 787192

I agree my comment was a little bit dry after re-reading it. That was not intended. My apologies.

I'm under the impression this is not the same bug as the one being linked in the original description. First, the feature is working in Ubuntu 10.10. Second, actually in Ubuntu 11.04, the feature is not working also for non WPA-protected network.

The following post seems to have a lot of valuable information concerning this issue:
http://ubuntuforums.org/showthread.php?t=1767958&highlight=MAC

I haven't tried the workaround you pointed yet for the reason mentioned above, but I can if you think, Mathieu, that it could solve the problem.

If you need any information to help you define this issue, simply walk me through it and I'll be glad to help.