Now THIS is what I call luck

Tales of my bad luck are legendary, and today is no exception.
For two months now I’ve been using my iPhone to send and receive email from various accounts, with no problems at all — it worked perfectly.
But now, today, mere hours before I am due to get on a plane and fly to DC, I can no longer send email. Jann spent a good hour poking around in my mail server looking for trouble, but nothing. And nothing changed on my iPhone. Hmm. So, I’ve completely wiped the phone and restored it to factory condition, then synced my mail accounts again. As before, it retrieves mail just fine, but can’t connect to send it.
Just my luck. The one time when I really need mobile email.