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I have heard of individual admins who have done something like this with SpamAssassin, they store outgoing IDs in in a database that's read during scanning. As it links outgoing mail with scanning it's more likely to be done on a proprietary basis which means it's hard to say who is doing it.
It's not completely safe either as it's possible to get IDs from mailing lists.
FWIW I used to configure my clients to use an anonymous looking free sub-domain in the message-id. If it showed-up in replies I took-off a few points in SpamAssassin, or handled it in sieve.
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