postfix/cleanup[9626]: 4413082E40: message-id=<20140220102521.4413082E40@mail.mmnc.co.uk> postfix/qmgr[9367]: 4413082E40: from=<double-bounce@mail.mmnc.co.uk>,size=255,nrcpt=1 (queue active)
你可以在这里找到更多细节……
http://www.postfix.org/ADDRESS_VERIFICATION_README.html