We are currently running Unity Unified Messaging 4.0(3). We have two locations with their own Unity servers connected to the same offbox exchange server. We need to go Unity VM only. Each location will have their own Unity VM only with onbox exchange 2000, in their own domain. The users currently are able to share and forward messages between the two sites. With 2 separate Unity VM only servers in their own forest what is the best way to allow the functionality of sharing or forwarding voice mails between the two sites?