We have a had mailman running for a while with our old email system and sometimes users will send a message to multiple mailing lists at the same time. For example. A user might send out a job posting email to both [list1] and [list2]. In our old email system, users that were subscribed to both lists received both emails. This is not happening for users that are in Zimbra. They are subscribed to both lists but only recieve one of the two messages. I'm guessing that Zimbra see's the message as a duplicate. Our users actual want both messages but I'm out of ideas on how to get this to work like the old system.