A method determines whether a given mobile communication device is eligible to register for a particular service. A first database tracks the equipment capabilities of various mobile devices. A second database tracks which regions, of a plurality, of geographic regions are eligible to receive the service....http://www.google.com.hk/patents/US20040248570?utm_source=gb-gplus-share專利 US20040248570 - Method for registering with a communication service
