I encountered this little caveat this morning, myself - in my situation, however, it was simply a matter of adjusting the SMTP server settings.
Enabling the SSL connection for outgoing mail, and changing the port it was using (in my case, setting this to
[email protected]:587 solved my problem. Apple doesn't provide a specific spot to enter an outgoing port number, but you can tag it onto the smtp server as shown above.
Hope this helps - this got me up and running, both via Wifi and EDGE.