We are a company that actually collects spam for analysis. What I would like to do is to forward all of our catchall and other spam lover accounts to a server on our private network. My Zimbra installation has an interface on the public Internet as well as one on a private network (10.1.1.0/24).
It seems like postfix wants to do a dns lookup on any mail transfers. I have tried adding the private network to "mynetworks" but it still does not work. Is the only solution doing a split DNS Setup? Any other ways to simply forward mail to an ip address on the private network?