Disclaimer to forwarded mails to external domain?

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Hello dudes,

I'm considering to implement a new feature in my Postfix Mail Filtering =
Gateway.

It would be great to add a disclaimer note to forwarded mails to an =
external domain. Since I'm already running amavisd-new, with all his =
friends, I was thinking to invite alterMIME to the party.

The tricky part is how to detected which messages are automatically =
forwarded to an external domain.

A quick example:

Our domain is mydomain.com and all mails received by [email protected] =
are automatically redirected (forwarded) to [email protected]. And =
when this behaviour is detected the disclaimer must be added to the =
received message message.

So the main question is: how to do this? And just in case: alterMIME is =
the best solution?

Thanks in advance,
Vin=EDcius Ferr=E3o=

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