MailShield not allowing email with Windows Mail or Thunderbird

So, I upgraded to Avast! 5 Free today, and after the reboot found that I can no longer send/recieve emails using either Windows Mail or Mozilla THunderbird. This all worked fine before the upgrade. I get the following error in Thunderbird:

“Sending of username did not succeed. Mail server mail.serveon.net responded: Invalid userid/password”

If I disable MailShield everything works fine. So, how do I tweak MailShield to properly scan my emails while allowing communication? ???

See if this applies to you.
http://support.avast.com/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=458&nav=0,1,82