It would have been easier if you'd mentioned your email software. Since you are using OE6 you can export the message as a single ".eml" message. While the OE 6 format in the "OutlookExpress" directory is unreadable by mortals the ".eml" format is standard mbox format. That can be fed directly into the unlearn process modulo a possible need to excise carriage return characters, an exercise left to the student.
{^_^} ----- Original Message ----- From: "John Fleming" <[EMAIL PROTECTED]> > I finally have a need to unlearn a message that was auto-learned. My > messages are in mbox format. How can I unlearn an individual email? Tnx - > John > >