SMTPGW.TAB

 "domain"[TAB]"smtp-gateway"[NEWLINE]

Examples:

 "foo.example.com"   "@axmsserver.org"

sends all mail for 'foo.example.com' through the 'axmsserver.org' SMTP server, while:

 "*.dummy.net"   "@relay.axmsserver.org"

sends all mail for ``*'*.dummy.net' through 'relay.axmsserver.org'.

The 'smtp-gateway' can be a complex routing also, for example:

 "*.dummy.net"   "@relay.axmsserver.org,@mail.nowhere.org"

sends all mail for ``*'*.dummy.net' through '@relay.axmsserver.org,@mail.nowhere.org', in this way: relay.axmsserver.org --> mail.nowhere.org --> @DESTINATION.