is your xmpp.domain (“Server Name:” in the admin console) a DNS name which one can resolve in the Internet (e.g. like igniterealtime.org) or do you use an internal name like “foo.local”?
If you are using an internal name then please don’t try to change the xmpp.domain as this leads to various problems. It’s possible but one must inform the users and modify manually all users, there are some posts about this in the forum.
With a name which is resolvable in the Internet you don’t have problem, anyhow you may need to setup DNS SRV records for the domain. If you don’t have one you should setup an internal DNS server for this domain to make sure that internal clients connect to the internal address (10.x/192.168.x) while external clients should connect to a public IP address. It may be wise to install a connection manager in the DMZ and connect it to Openfire. This should result in two scenarios:
Client(Internet)__Firewall__Connection-Manager(DMZ)__Firewall__Openfire(LAN/inte rnal DMZ)
If you get problems with Internet clients you can simply shut down the connection manager.