Milter-greylist

Does anyone know how how to grey list a sender when the Message-ID header is empty, or not even present at all?

(Note: I'm using milter-greylist with Postfix)

I have tried various combinations, but none of those conditions ever match:

dacl greylist header /^Message-ID:!(.*)/ msg "empty message id"

dacl greylist header /^Message-ID:$/ msg "empty message id"

dacl greylist header /!(Message-ID)/ msg "missing message id"

Also, just as a test, I searched for a random string in the headers, "greylist" action doesn't do anything at all (just let the message pass), and "blacklist" drops the message on the server side, but returns a "message queued" to the client.

Any thoughts?

Thank you.

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