I have 2 sites, each with its own forest and domain. Each uses Exchange 2003. And I have setup a permanent VPN tunnel between the two site with a bi-directional trust and dns.
When I want to send an email to emails for "...@siteb.com", my exchange on siteA sends it to the internet and it gets delivered to siteB. Is there a way to set up a link (connectors, smtp virtual server or something) in the Exchanges of my 2 sites so that mails sent to @siteb.com gets emails sent directly to the exchange of siteB using the vpn tunnel, all all other emails gets sent as usually to the internet (and vice-versa of course)?