We have several build servers connected to a single management server. Currently it appears that every server must be the exact same version or the build servers cannot connect to the management server successfully.
It's royal pain having to update all of our servers in order to get one server updated to use a new feature or a bug fix.
What I'd like to see is more lenient protocol allowing for example servers to communicate even if their exact versions do not match. Also the error handling in situations where the versions do not match could be improved, so that instead of throwing up a stack trace the servers would communicate clearly that the versions do not match.