Method and apparatus for processing location service messages in a satellite position location system is described. In one example, a mobile receiver includes a satellite signal receiver, wireless circuitry, and at least one module. The satellite signal receiver is configured to receive satellite positioning system signals, such as Global Positioning System (GPS) signals. The wireless circuitry is configured to communicate location service messages between the mobile receiver and a server through a cellular communication network. The location service messages may include any type of data related to A-GPS operation, such as assistance data, position data, request and response data, and the like. The at least one module is configured to provide a user-plane interface and a control-plane interface between the satellite signal receiver and the wireless transceiver. The at least one module is capable of processing location service messages communicated using either the control-plane signaling or user-plane signaling mechanisms.