[Mailman-Users] Reply-To list and poster in _some_ headers

[david gordon]

I have a 2.1.5 Mailman list set up so all replies go to the list. The
setting "Where are replies to list messages directed? Poster is strongly
recommended for most mailing lists." is "Explicit address" and the
"Explicit Reply-To: header." is the email address of the list, ie
list at mydomain.tld.

Everything seems fine and this worked okay in MM 2.0.13. Having just
upgraded to 2.1.5 I see a couple of messages reaching the list with a
Reply-To header of

>Reply-To: list at mydomain.tld, original_poster at theirdomain.tld

Any ideas why this should be?

Thanks

david gordon