Mailman should add a Received header
Original LP Author: Barry Warsaw , LP Link: https://bugs.launchpad.net/bugs/885715
When the LMTP runner or any other injection vector receives a message, it should add a Received header to indicate the time at which Mailman got the message. Use case: there is a spam filter between the incoming MTA and Mailman, and the message sits in the spam filter for a while before its administrator accepts the message.