Exchange Exchange

Now I've got to explain that subject line

I'm looking at a scenario where a client has 2 networks with NO network connectivity between them, but regular email flow. This is accomplished as follows:

 One network (the isolated network) has an Exchange 2003 organization; for any email that's going outside that network, E2K3 sends it to Sendmail smarthosts. The email queues up on the smarthost, and the files in the Sendmail queue directories are moved to the other network via a file transfer system which connects to one network at a time. On the destination network, the files are put on a Sendmail server there, and Sendmail then processes the messages and delivers them appropriately. The destination network has an elaborate Sendmail-based system to route messages depending on whether they are bound for hosts on that network, or for Internet (external) hosts; there's no Exchange on this network at present. There is also email from this network back to the isolated network that does presently contain Exchange 2003.

My challenge is coming up with a system based on E2K7 that will work with this; the goal is to remove all Sendmail from the environment and implement E2K7 orgs on both networks. One approach I've thought of is this:

1. Deploy Hub Transport servers in both networks to accomodate intra-org (internal to that network) mail flow.
2. Deploy Edge Transport servers in both orgs to accomodate inter-org mail flow (mail between the networks).
3. Use scripts to move the queue databases between the edge transport servers via their file transfer system to the destination organization and replay them, using the procedures outlined at http://technet.microsoft.com/en-us/library/bb124343(printer).aspx

Anyone have any thoughts on this approach? Or, any suggestions for another approach?

Thanks,

Andy