John W. Baxter wrote:
>>>> curious about the second: can a message really get to the delivery
>>>> point without a Message-ID header?
>>> If I remember well, only in submission-mode exim should do some
>>> fixups (Message-ID, Date, Sender, ...).
>> Yes, I remember setting that option a few years ago on my outgoing
>> exim. ISTR (but I could be wrong) that I needed to do it because
>> messages were getting rejected by subsequent mail servers for not
>> having MIDs.
>
> [Catching up]
> Unfortunately, having a Message-Id: header is still a SHOULD, even in RFC
> 5322. So one really ought not to reject based (only) on their lack. It would
> be very nice if I could. (And if running a server only for myself, I likely
> would, with provision for an exception list.)
My first stop when considering how much of a spammy indicator a metric
is, is to check out what the default SpamAssassin score is for it. When
SpamAssassin notices a message without a Message-Id header, it *does*
note it in the report, but it doesn't actually apply a score. Ie:
0.0 MISSING_MID Missing Message-Id: header
I'm assuming that there is a lot of ham out there with missing
Message-Id headers, or SpamAssassin would be assigning at least a score
of 0.1 for it...
Perhaps they put it in the report so it can be used for bayes.
--
Mike Cardwell - IT Consultant and LAMP developer
Cardwell IT Ltd. (UK Reg'd Company #06920226)
http://cardwellit.com/