Outlook 2003 - IMAP messages & winmail.dat

I have a perplexing issue with Outlook 2003 that I'm hoping someone can help with. It is a known that OL cannot be forced to store Sent Items on an IMAP server. Therefore I wrote a rule per the Microsoft KB instructions to place a copy of sent messages in the IMAP store's Sent Items folder. This worked well enough in OL2000. I have now upgraded to OL2003. Suddenly all sent messages stored on the IMAP server (via the Outlook rule) contain the dreaded winmail.dat attachment when viewed by anything other than OL (like my web based client for remote access). I am setup for Text Only format, no special forms, and default encoding. The outgoing messages do not contain the winmail.dat attachment at the recipient's end, just the stored version on my IMAP server. So long as there is no real attachment with the message, it is just an annoyance. However, any real attachments are wrapped up in winmail.dat and are not accessible. I have verified that this does not occur with HTML formatted messages, just text-only messages.

I've looked at every format option I can find but nothing helps. I found this KB article that confirms something about storing text-only messages on an IMAP server and winmail.dat but no solutions. http://support.microsoft.com/default.aspx?scid=kb;en-us;280857

There must be solution since I can't find Microsoft hate articles all over the internet about this. I have a hand full of OL 2003 installs in my office and they all exhibit the same behavior.

Any ideas?

Keith