dotcomUNDERGROUND

Download Windows Live Messenger 8.0.0365 BETA

Download directly from Microsoft: http://download.microsoft.com/download/4/2/3/4236042d-176d-4a69-a60a-e40f768e3500/EN/Install_Messenger_Beta.exe

If you are not an official beta tester or dont have an invite you will also need to install LiveConnect V4 from here:
http://www.filelodge.com/files/hdd4/61968/LiveConnect%20v4.zip

It will bypass your connection.