This is a question that has been asked for years! 

Unfortunately at this time that requested feature is not available, but it's certainly been asked for.

I believe they haven't tried doing this because of legacy clients. There are still plenty of customers out there who have upgraded their servers but still have very old versions of the clients on their PC's because of various factors. If they changed this they'd have to be extremely careful that they do not break functionality on their old clients.