Different server versions together?

We are currently running a Lotus Domino server version 5.0.12 and might need to add another server for the Blackberry Enterprise Server. If we purchase another license of Lotus Domino it will be version 7. Is it possible to run two completely different versions of Domino together on the same Lotus domain or would we need to upgrade our existing server software first?

Any input would be greatly appreciated.

Thank you!

Subject: Different server versions together?

You just need to make sure you don’t upgrade the design of your name and address book to version 7. I imagine the version 7 address book would not run on the version 5 server. Otherwise, it should be fine.