gnome-shell's network applet is a bit unfinished.
1. disable the gnome-shell's network applet, reverting to the old network-manager applet (nm-applet) by doing sudo mv /usr/share/gnome-shell/js/ui/status/network.js /usr/share/gnome-shell/js/ui/status/network.disabled and execute (via alt+F2) the command 'r' (without quotes), to reload gnome-shell.2. run nm-connection-editor to edit the connection (or right click the network icon).
reference: http://askubuntu.com/a/86508