The SSP CM and Engines currently have to be on the same point release to function. This prevents a customer with a large installation base from gradually upgrading their environment. We have one CM with cold fail over and as many as 24 Engines attached to that CM. Today to upgrade we have to upgrade both CMs and all 24 engines in a single change window. One component or the other should be able to be upgraded first to allow gradual upgrades in large environments. Running dual CMs isn't an option as there is no way to keep common configurations in sync nor is there a way to move configurations from one CM version to another, only through an upgrade.