Minor Description
I added support for a further parameter to the <account /> tag: customrcpt-header.
There are many MDA that will not add the "for" statement in the received header but they will add an header "X-Envelope-To" or "Received-For" or something similar with the content of the RCPT for that message.
using:
<account user="<USER>" password="<PASS>" recipient="<RECIPIENT>" ignorercpt-header="false" customrcpt-header="X-Envelope-To" />
will use the content of X-Envelope-To instead of the received for to get the intended recipient.