non-existent msgids & duplicate delivery suppression

Stephen Grier s.e.grier at
Fri Jun 27 11:25:29 EDT 2003

On Fri, 2003-06-27 at 14:10, Sebastian Hagedorn wrote:
> -- Stephen Grier <s.e.grier at> is rumored to have mumbled on 
> Freitag, 27. Juni 2003 13:47 Uhr +0100 regarding non-existent msgids & 
> duplicate delivery suppression:
> > I have noticed that this has been happening on other occasions, where
> > lmtpd does a duplicate_check and then a duplicate_mark on zero length
> > message-ids. This raises the possibility that the server is suppressing
> > messages that are not duplicates, but merely have no message-id header.
> That in itself is very weird. Every MTA along the way should add a 
> message-id if there isn't one. Or are you saying there *is* a message-id, 
> but it's empty? That would be horribly broken, but might explain why one 
> isn't added by the MTAs ...

Yes, the messages do have a Message-Id: header with an empty value. I've
identified 2 domains which appear to be doing this.

Would it be reasonable to have lmtpd not add an entry to the deliver db
for zero-length message-ids?


Stephen Grier
Systems Developer
Computing Services
Queen Mary, University of London

More information about the Info-cyrus mailing list