I'm working for a Europe based financial company (around 80.000 mailboxes worldwide). We have our mailboxes spread over several mailbox systems, mostly Exchange but Domino is also used. Some are large others are very small. We have interconnected the systems by putting a mail relay layer between the mailbox systems and the internet gateways (Ironport).
This middle layer provides us content filtering, address rewriting, virus scanning and some special functions like a customized Out of Office system.
I assume some other companies are using a similar setup and like to know what products are used for it. and.... of course.... what are your experiences.
Thanks for your reaction!