If I am not mistaken, it's a MTA and not a MLM that did that modification.
Right, it's Courier. DKIM has now been a published RFC for three
years, and was in development for several years before that, and this
is the first time we've run into this sort of incompatibility.
Under the circumstances, the correct response is clearly to fix
Courier so it doesn't mess with the mail headers it presents to
milters rather than to modify DKIM and change every DKIM
implementation in the world to work around it.
R's,
John
PS: I think you'll find this is not the first time Mr. Courier has
provided this sort of unasked help to his users.
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