I created an adhoc WIFI network with WEP2 on windows 7 with a 25 character key
I share a sierra wireless connection from ATT.

I see the wireless connection on ubuntu, but when I click on it nothing happens.
Using a vista machine , I had no trouble connecting and using the connection.

I am able to connect to a normal wireless network, just not the vista adhoc

I am running Linux ubuntu 2.6.35-22-generic #35-Ubuntu SMP Sat Oct 16 20:36:48 UTC 2010 i686