[Exim] Header/Envelop question

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Hello,

I have two little question about headers and the envelop when using mail
lists.
When sending mails to a mailing list the name of the list is written to
the To-header (or CC) and not my real e-mail address - this is ok since
the MTA uses the envelop (with my real address) to send the mail. As
soon as the mail is delivered there is no trace left which the final
mail address was - only the address of the list is left (because the
envelop is only needed for the MTA). This is ok and works in 99% of all
cases.
Now I found a case where this does not work. A service provider collects
all incoming mails in one mailbox and delivers the mails to their users
by looking up the To and/or the CC headers (not the ones frome the
envelop since this information is already deleted). In the To-field only
the address of the list is found and the mail is undeliverable.
Coming to my questions:

1. Does the service provider follow any standard? I think not. But i
would like to know where to find the RFC. Or any other documenation I
can prove that the behaviour of exim in this case is correct and that
the MTA of the service provider...

2. Can I get the exim to rewrite the header in some form (for example
add a header) with the addresses which are used in the envelop?


Greetings, Jan Suchanek

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Jan Suchanek,
Universitaet Ulm
Abteilung Medieninformatik
Fakultaet fuer Informatik

89069 Ulm, Germany
Raum: O27/3302

Tel.: +49/(0)731-5031312
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