Comment 15 for bug 1604181

What we want to see is an email from his phone, not one from the list sant from his phone. I.e., we want to see the original Reply-To: from the phone.

I actually use K-9 Mail on my Android phone. I think it is excellent as mobile device MUAs go. But K-9 isn't the issue. The issue is what he has set as the Reply-To: address in the account he's sending from.

For Ubuntu packages, see http://packages.ubuntu.com/search?keywords=mailman. Also see <https://wiki.list.org/x/17891606> about upgrading from source, but I don't think that will change this behavior although 2.1.18+ will allow you to Munge From only from domains with DMARC policy. Setting first_strip_reply_to = Yes will probably fix this for you and will still add the original From: to Reply-To:.