What is Subversions pre-1.0 interoperability policy?
For the WebDAV network layer: the client and server are guaranteed to work as long as they aren’t more than one major release version apart. (For example, a 0.25.X client will talk to a 0.24.X or 0.26.X server.) For the custom ‘svnserve’ network layer: the client and server must have identical release numbers.