This is something I have wondered about Android OS/Hero/Sprint since day one of my purchase, but I have never brought it up here. When mobile network is off and WiFi is enabled, I cannot retrieve my Yahoo Mail. It has never really bothered me, because when mobile network is connected and WiFi is off, my mail app (which is connected to Yahoo - I don't use Gmail) worked perfectly fine. Can anybody explain this to me? Does anybody else use Yahoo as their email server and has the same issue? Is it just Google sticking it to their customers and to Yahoo by saying "ok, if you wan't to use our (#1 competitor's) email service, then we will make it so it will only work on Mobile Networks. Thanks for all of the input!