1 x Windows Server 2003 x64 running Exchange Server 2007 Std (Version 8.1 - build 240.6)
1 x Window Server 2003 running Exchange Server 2003 Std (SP2)
Servers are in separate domains, but a forest level transitive two way trust exists. They are on the same subnet of a network with no firewalls between them.
Two separate organizations have recently moved into the same building. They are sister companies, with open trust between the two. There is a requirement for some members of both companies to have mailboxes on the 2 exchange servers and more importantly, they need to be able to setup meeting room mailboxes to automatically schedule meeting room requests.
I do not know how to setup such a relationship, and would be grateful of any guidance.