I did a branch on the 2.1 series to test rewriting the From: header to be able to make emails to comply with DMARC and ADSP
You can find the branch here:
https://code.launchpad.net/~mlm-author/mailman/2.1-author
and the diff with mailman main branch here: http://bazaar.launchpad.net/~mlm-author/mailman/2.1-author/revision/1340?start_revid=1340&remember=1338&compare_revid=1338
I have also a test mailing list running at: http://lists.peachymango.org/mailman/listinfo/mlm-auth
The best to see how it works is to subscribe, send an email, and see how the email is distributed. I guess you need to receive an email to see that... I'll reply...
Several ways to solve this problem were explored with mailman: http://wiki.list.org/display/DEV/DKIM
I took a 7th option which is to rewrite the From: without using the + and put the information about the sender in the Reply-To:
This may not be optimum but it works.
Overall this solution is one out of 3 ways to get mailing lists running with DMARC (see DMARC FAQ)
- don't break DKIM
- use AOR
- rewrite the from
There is another one which is to whitelist emails coming from mailing lists....
Also note that while I'm involved in the DMARC group, I do this code as a personal project.
Now send comments, and be nice with me :P