Subject prefix-ing not always working

Hi:

Per FAQ 8.3, adding text to the Subject of list messages [which I've always used
succesfully in the past] via rc.local.s20 [see way below]:

On the most recent list I've set up, some messages contain this text and some DO
NOT.  Both senders are on dist, I don't think I see any differences in the
headers, and I can't figure out what makes one different from the other.  Has
anyone seen this before, or does anyone have any suggestions for what I might
look into to resolve?

Thanks, Mitch
------------------------------------------
SUBJ=`formail -zx Subject:`   # extract the subject
          :0fw
          * !  Subject:.*\[Focusing, Contemplative Practices and Spiritual
Paths\]
          * !  Subject:.Re: *
          | formail -I "Subject: [Focusing, Contemplative Practices and
Spiritual Paths] $SUBJ"
#
     # Appending a footer to every outgoing mail:
     #
     :0 fbw
     | cat - footer.txt
----------------------------------------
Mitchell Darer, Systems Support / List Manager,  [email protected]
The Focusing Institute, 34 East Lane, Spring Valley, NY 10977
http://www.focusing.org  (845) 362-5222,    fax(845) 678-2276