I was having an issue with the "Connect to Hidden Wireless Network" dialog the connect button was greyed out. It was a pain to connect, so a bit of searching turned up a bug on Launchpad. The bug on launchpad that fit the description https://bugs.launchpad.net/ubuntu/+sour ... bug/446394.
What fixed it for me, was to add the PPA for Network-manager.
Code: sudo add-apt-repository ppa:network-manager/ppa
I did an update/upgrade
Code:sudo apt-get update && sudo apt-get upgrade
Then a reboot, now I am able to select connect button to connect my hidden wireless network.