Hi,
We are running a mailman 2 mailing list, soon to upgrade to mailman 3. We recently switch the mail gateway from mailgun to Amazon SES. There's a new problem that the mailman 2 archives are not able to group threads together the way they were before. Moreover, end users have their own mail clients that display the list messages, and they are complaining about issues in their local mail clients. It seems to be related to the mail header fields Message-ID: , References: , and In-Reply-To: .
Amazon SES rewrites the Message-ID.
Therefore, it won't match the original Message-ID, and so the second reply email won't matched with the first email in a web archive display. Additionally, email replies are often sent both to the list and to individual participants, and so it's important that both of these copies have the identical message id.
Has anyone else used Amazon SES as a mail gateway, and did you have success with it? Does this interpretation of the problem seem reasonable?
Would it make sense to briefly discuss "Amazon SES" in an FAQ section of the mailman documentation?
Thanks, Sam