Talk:Friends/@comment-96.20.211.72-20120918215041

How to invite friend by gamecenter? This sounds like a ridiculous question, yet I am puzzled. All I'm trying to do is inviting friends to gift gems to, but I only have their gamecenter ID. Right now I'm trying to go to : friends -> invite friends -> and all I see is "facebook", "email", "text msg".... how can you enter gamecenter ID??????