A third generation (3G) mobile communication system supports an over-the-air activation scheme utilizing a wireless packet data protocol. A subscriber identity module (SIM) is preloaded with temporary operating parameters such as a temporary international mobile subscriber identity (IMSI) that is used for initial access to a network. Once a packet data protocol communication link is established between the mobile device and a network support node, the user may remotely subscribe to a number of service terms using the mobile device. In addition, an activation procedure is carried out to assign permanent operating parameters, e.g., a permanent IMSI, to the SIM. After activation, the user can remotely modify existing terms or remotely enroll in additional service features via a wireless IP link between the mobile device and a network support node.