On Wed, Oct 28, 2015 at 04:06:26PM +0100, ma...@stoecker-family.de wrote:
> I do not understand your question.
> I configured mailman as a mailing list server using postfix (relayhost) and
> fetchmail as its interfaces to the internet as described for mailman.
Not all the question you're being asked are relevant. Focus on
fetchmail, that's the source of the problem.
Mail to 5 recipients is stored in the upstream mailbox as 5 messages,
one delivered to each recipient. However, somewhere between the
upstream store and the fetchmail client, the recipient address is
lost. Instead fetchmail erroneously delivers each message to all
5 recipients from the "To:" header.
This fetchmail configuration is broken. It fails to deliver Bcc
mails, it erroneously duplicates messages.
The upstream mailbox MUST record the envelope recipient of each
delivered message in a way that's understood by fetchmail, or
it is not suitable for this purpose (no multi-drop support).
--
Viktor.
