If you change the language and press Apply, the buttons "OK", "Cancel", and "Apply" don't change, and the tabs at the top don't change. Also, the title where it says "Preferences" doesn't change. I know when you click Apply it says "You'll need to restart Messenger for some of the changes to take effect," but if most of it changes on Apply, shouldn't it all? And since it says "Messenger" and not "Messenger Plus! Live," I'd assume it's not telling you that you need to reopen the window to see the changes.