My iPhone 4S can receive e-mail addressed to my RoadRunner account when I am not connected to my personal WiFi base station, but I cannot send messages or replies until my phone is back in touch to my home WiFi. (Or I can send the reply from my mac.com e-mail address, but this does not help my wife, who has an iPhone 4s but does not have a mac.com e-mail account.)
The RoadRunner POP account on my iPhone uses pop-server.nycap.rr.com as the Incoming Mail Server and smtp-server.nycap.rr.com as the Outgoing Mail Server. I do not have anything defined as an Other SMTP Server.
I have tried to add iCloud SMTP Server as an Other SMTP Server, but that doesn't work because the on-screen keyboard does not include a space bar.
View the Correct Answer How can get my phone to send mail through RoadRunner accountnvia 3G in iPhone Correct Answer , Solve the iphone Mail, Contact , Calendar problem