Sadly not - <sample>
From MAILER-DAEMON Mon Jul 19 13:22:20 1999
Date: Mon, 19 Jul 1999 13:22:20 +0100 (BST)
From: Mail System Internal Data
Subject: DON'T DELETE THIS MESSAGE -- FOLDER INTERNAL DATA
X-IMAP: 0932386940 0000000000
This text is part of the internal format of your mail folder, and is not
a real message. It is created automatically by the mail system software.
If deleted, important folder data will be lost, and it will be re-created
with the data reset to initial values.
Actually I think the message is created by pine, but in any case
it's done when I save messages to a folder so procmail wouldn't help.
procmail could still be a solution. Instead of calling MHonArc directly,
'| /usr/bin/procmail -m /etc/mail/mhonarc.procmailrc'
if you add in realtime (via -add or somesuch), or
'formail -s procmail -m /etc/mail/mhonarc.procmailrc < mbox'
if you're processing an entire mailbox at a time.
/etc/mail/mhonarc.procmailrc might look something like
* ! ^Subject: DON'T DELETE THIS MESSAGE -- FOLDER INTERNAL DATA
| $MHONARC $MHONARCARGS
Or like you said, preprocess with perl or sed. I'm not sed-aware
enough to do that, so
| perl -pe 's:^(Subject\:.*DELETE THIS MESSAGE -- FOLDER INTERNAL
DATA$):$1\nX-no-archive\: yes:g' | mhonarc ...
should work just as well.