1. A method of providing interoperability between an open standard directory service and a proprietary database comprising the steps of: configuring a mapping tree node associated with said proprietary database to replace root of said mapping tree and to replace default backend of said service with said proprietary database; configuring a core server of said directory service to recognize said mapping tree node associated with said proprietary database as root of said mapping tree; routing all directory service operations to an object that handles operations in said proprietary database; and redirecting remaining operations to said core server by said object, so that default server functionality is preserved.