Hello. I have the next situation. I have two forests. Each of has one tree with one second level domain. There is a trust relationships between forests. There is deployed Front-End Back-End topology into one of them. And there is a basic topology in another one. Only Front-End server has possibility to perform mail exchange with external sources. I want to direct external mail flow from/in basic topolgy through the Front-End server of another forest. Could anybody give any advice of performing this task. Or just give a link to description??? Thank you.