This white paper demonstrates how to identify and resolve IBM Lotus Domino 8 mail routing problems. By explaining how and which debug to use, and how to analyze the debug output, it is intended to help customers debug mail-routing issues on their own. Support Engineers can also benefit from this paper by enhancing their understanding of the debug outputs and by using it as a "cheat sheet" in identifying and resolving common mail-routing issues...

Source: http://www.ibm.com/developerworks/lotus/documentation/domino/d-ls-mailrouting/index.html