A method and apparatus for configuring an element management system server (an EMS server) to support new network element service application versions without upgrading the EMS server software is provided. The EMS stores base version data that describes the data model of a first version of a service application installed on a network element. When a second version of the service application is available, incremental version data describing changes to the data model from the first version to the second version is obtained and stored. In response to receiving a client request involving a service application on a particular network element, the EMS may apply incremental version data, associated with the version of the service application installed on the particular network element, to the base version data to form merged version data that describes the data model of the version of the service application installed on the particular network element.