How can I delete Resent headers?

I am using EXIM and smartlist to manage some lists. Messages come into
listname, exim delivers it to smartlist (flist), smartlist processes it
and mails it back out to listname-dist. During the process, headers for
Resent-From, Resent-To & Resent-Sender headers are added to the outgoing
messages.

Now when the end user replies to the message, it picks the addresses out
of the Resent-To (listname-dist) and Resent-Sender (listname-request)
headers.

How can I remove these headers from the outgoing mail.

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* Joe Metzger                          Ames Office: (515)294-1939       *
* Computer Systems Engineer            LBNL Office: (510)486-5740       *
* Network Information Services Group   metzger@???                   *
* ESnet, Lawrence Berkeley Laboratory  314 Wilhelm, ISU, Ames IA, 50011 *
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