sort: mail default (mailWindowOverlay.js) or Mailbox Default (INBOX.MSF)

I see from the MSF definitions (in any given mailbox) that B0=sortType,
and is used as follows (from 1.5):

SORT BY DATE DATE
@$${51{@
[1:^9E(^B0=12)]
@$$}51}@

SORT BY RECIEVED
@$${51{@
[1:^9E(^B0=15)]
@$$}51}@

Above the significance to me seems to be that a "serialized" action
(launching mail, changing sort, closing mail) gets appended to the MSF,
which includes the last chosen option stored, such as View | Sort |
Order Received (sortType == nsMsgViewSortType.byId in mailWindowOverlay.js).

On a newly installed Mozilla 1.5 system, I can change the last
[1:^9E(^B0=15)] and it will accurately change my sort order for that
mailbox/folder. How can I make this persist (ie, be a default for the
folder or all imap folders) through either the MSF or another method?

My only desparate thoughts revolve around grabbing the last
"transaction" and adding the sort (BO=15) to that entry (or changing it
if it does not exist) - something that would have to be done for every
folder to make it worse. Actually just doing it to the INBOX.MSF seems
like a lame hack to do.

 From prefs.js can I do a
user_pref("mailnews.viewLabelMenuItem.setAttribute("sortByOrderReceivedMenuitem", 

"checked") or something similar?

Misc notes:
1. There is nothing that is changed in the prefs.js file or anything in
one's local profile excepting the MSF file itself.
2. One cannot set a default sort through the GUI (not selecting a
mailbox disables the menuitems).
3. http://www.mozilla.org/unix/customizing.html#prefs lists nothing
related to sorting. Likewise can't goodle anything on hidden sort
options in prefs.js.

Part of this need was initiated by bug #73565
(http://bugzilla.mozilla.org/show_bug.cgi?id=73565) but now it has
surpassed this base requirement. If that bug gets resolved (or I
procmail all our mail to build a valid date header), it would help some
but honestly there's a larger End-user training issue here in our
migration attempts away from Outlook to Mozilla. Discrepancies in
handling are one part, but so many of our users are Outlook born and
bred that they have made the sorting default a thorn.

Plus... the technical curiousity is driving me mad... it 'must' be
possible (without src modification recompiling)...

Thanks for any and all assistance!

Best,

Matthew Kurowski