I've confirmed this in oneiric (0.9.1.90-0ubuntu6) and precise (0.9.1.90-0ubuntu7).
I glanced at the network-manager-applet code and believe that wpa-none should be supported for ad-hoc networks. I don't see any obvious fixes in the upstream git repo, nor any related upstream bugs. However, I did find this interesting comment in the bug tracker: https://bugzilla.gnome.org/show_bug.cgi?id=654772#c1 ** Bug watch added: GNOME Bug Tracker #654772 https://bugzilla.gnome.org/show_bug.cgi?id=654772 ** Changed in: network-manager (Ubuntu) Status: New => Confirmed -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to network-manager in Ubuntu. https://bugs.launchpad.net/bugs/905748 Title: Create WPA2 adhoc is Open, not encrypted Status in “network-manager” package in Ubuntu: Confirmed Bug description: When I create a new network with networkmanager, select wpa2 personal and enter a password, the network that gets created is actually Open. In the connection information on Ubuntu, the network ist shown as WPA2 secured, but I can connect with other devices without entering any key. The network is discovered on windows and on Android (CM7) as OPEN! Using ubuntu 11.10, network-manager 0.9.1.90-0ubuntu5.1 I couldn't find any reference to this behaviour on the net or in the bug tracker. bug 322902 seems similar Note: With standard Android, it's not possible to connect to an adhoc wifi. With cyanogenmod or other mods it's possible. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/905748/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp