I don't know of any add-in to do this. The code would look something like the example at http://www.outlookcode.com/d/code/convertfields.htm

Signature
Sue Mosher, Outlook MVP
Author of Configuring Microsoft Outlook 2003
http://www.turtleflock.com/olconfig/index.htm
and Microsoft Outlook Programming - Jumpstart for
Administrators, Power Users, and Developers
http://www.outlookcode.com/jumpstart.aspx
> Hi,
>
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>
> Mario