1. Go to your Documents\My Games\Unreal Tournament 3\UTGame\Config folder. 

2. Find UTEngine.ini and delete it (OR open it up and delete the [OnlineSubsystemGameSpy.OnlineSubsystemGameSpy] section). 

3. Run UT3 and it will ask you for a CD key. Enter 225L-HTBT-3K2S-3EEY

4. Connect to our server.