Re: [Exim] Writing uniform Message-IDs

>From: "J.D. (Jack) Bitters" <JDBitters@???>
>To: exim-users@???
>Subject: Re: [Exim] Writing uniform Message-IDs
>Date: Thu, 5 Aug 2004 05:06:14 -0700 (PDT)
>
>As the poster who started this thread, I thank all who replied.
>
>All your answers and comments are greatly appreciated and will help us
>decide whether to switch from Postfix to Exim.
>
>I noticed that more than one poster mentioned "control=submission" as a
>possible solution. I found nothing in the Specification on the subject.

It's in Section 38.11 of the exim4.40 specification.