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Re: greylisting done at end of headers, or end of daya (QUIT) ?

2007-01-30 15:19:07
On Tue, 30 Jan 2007 12:40:20 PST, "william(at)elan.net" said:
Who exactly generates new Message-ID per each transmission???
Its true that some messages come with no message-id and then my MTA
would add one in, but ones the field has been added, I'd not expect
it to be removed if message is retransmitted further.

No sane properly-behaving standards-conformant MTA would do that sort
of nefarious change, because it would totally busticate any software that
was trying to use the Message-ID: for duplicate detection.

But remember that spammer software is (a) not properly behaving (if it was,
greylisting wouldn't work - it relies on the fact that most spamware won't
requeue and retry), (b) not standards-conformant, and (c) being run by people
who have a vested interest in doing everything they can to prevent you from
detecting the current message as a duplicate of anything else....

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