LISTSERV uses information from DOMAIN NAMES to determine to which gateway the stuff would be going, and forwards it to the nearest LISTSERV, which in its turn transfers it to its local MAILER who'll forward it to the gateway defined in DOMAIN NAMES. To use a nearer gateway you must change DOMAIN NAMES in such a way that your server believes it is the nearest LISTSERV to the gateway, and have your MAILER use that gateway by default too. Or use explicit routing with the % hack. Eric