Namespaced code with SabreDAV

Hello all, I am trying to use the wonderful SabreDAV library to create a webdav share. I have a demo up and running however the framework / class i'm using is namespaced, and SabreDAV unfortunately does not have a 5.3 style namespace declaration. I have an spl_autoload function registered in my base controller and so long as I prefix the classname with a \ it all works: $rootDirectory = new \Sabre_DAV_FS_Directory($rootDir); // The server object is responsible for making sense out of the WebDAV protocol $server = new \Sabre_DAV_Server($rootDirectory); However, SabreDAV it's self has a large amount of other PHP classes which it calls which obviously aren't prefixed with '\' Is there a way i can tell PHP any class name that get's instanciated with 'Sabre_' should resolve to '\Sabre' ? Many thanks Andrew