Adding to a field?

        What the best way to add to a field with procmail, formail?  I 
want procmail to send some messages to formail so it can add an 
additional address to the Reply-To field. E.g.:

        Orig:
        Reply-To: john(_at_)somewhere(_dot_)com

        New:
        Reply-To: john(_at_)somewhere(_dot_)com, 
mary(_at_)somewherelse(_dot_)com

        Is there a smooth way to do this?

---
Jeffrey Gustafson -- jeffgus(_at_)packardbell(_dot_)com
Technical Specialist & SysAdmin
On-Line Services Group
Packard Bell Electronics, Inc.