[Mailman-Developers] FAQ 1.9. What does "message has implicit destination" mean?

[Brad Knowles]

Folks,

	I've been trying to debug a problem we've seen recently on one of 
our mailing lists, and ran across this FAQ entry (at 
<http://www.python.org/cgi-bin/faqw-mm.py?req=show&file=faq01.009.htp>) 
which seems to have a relevant paragraph:

		The reason this happens is that mail being distributed by a mail
		list retains the name of the mail list in the To: header and the
		name of the original sender in the From: header. So, when the
		mail gets to the sub-list, it is still marked as being To the
		umbrella list. By entering the name of the umbrella list as a
		valid alias, you tell your sub-list that it's OK to accept mail
		which was originally sent to the umbrella list.

	In particular, the problem I've been trying to debug was a 
message I had sent to a particular person which was cc'ed to the 
mailing list.  By the time the mailing list recipients got the 
message, the mailing list address had moved from the "Cc:" header to 
the "To:" header, and the original contents of the "To:" header had 
gotten destroyed.  I rooted around in the raw message archives, and 
the message was actually received with the correct addresses, so it 
must have been Mailman that did some header scrubbing of some sort.


	I've looked through CookHeaders.py and SMTPDirect.py, and other 
files under the mailman/Mailman directory tree, and I haven't found 
where this behaviour is taking place.

	Can someone help me understand why the original contents of the 
"To:" header would be destroyed and replaced with the mailing list 
address, as opposed to having the contents of the "To:" header placed 
on the "Cc:" header and then the mailing list address placed in the 
"To:" header after this data was moved to a safe location?

	Can someone help me understand where this modification is 
actually taking place, so that I can fix this bug in our copy of the 
code?


	Once I understand better what is going on, why, and where, I can 
file a bug report with SourceForge, along with a suitable suggested 
patch.


	Thanks!

-- 
Brad Knowles, <brad.knowles at skynet.be>

"They that can give up essential liberty to obtain a little temporary
safety deserve neither liberty nor safety."
     -Benjamin Franklin, Historical Review of Pennsylvania.

   SAGE member since 1995.  See <http://www.sage.org/> for more info.