We've run into TWO customers at the same time who want to add failover partner servers to their existing Unity 4.0(x) deployments. They've both got shiny new MCs-7845H servers (DL380-G5) and they shipped with a Windows 2003 image. The existing servers are running Windows 2000. One of the customers is VM-only Exchange 2000, the other customer is UM with Exchange 2003.
Regardless of Exchange, can we have Unity failover partners running different operating systems? (Windows 2000 and Windows 2003). I searched documentation on this without success.