I have the problem described as above also. I am running a BCM94306 network card. I can connect perfectly at home (WPA2-PSK) but when I attempt to connect at school (public network) It will not connect. This is a completely fresh ubunto dapper install with all updates applied and network manager installed.
-- Cannot associate with unencrypted networks using bcm43xx chipset (ndiswrapper driver) https://launchpad.net/bugs/42504 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs