You may consider restricting access to mail-gateway to localhost by default, as
recommended in upstream wiki documentation:
(Handling incoming mail)
If you think restricting access by default is not a good idea, it may still be a
good idea to add sample configuration to default httpd rt3.conf.
This package has changed ownership in the Fedora Package Database. Reassigning to the new owner of this component.
rt3 was retired on f21 and rawhide.