Some embodiments are implemented in a communication system that includes a first wireless communication system and a second wireless communication system that includes a Femtocell access point (FAP) and a network controller that can communicatively couple the FAP to the first wireless communication system....http://www.google.com/patents/US20080076420?utm_source=gb-gplus-sharePatent US20080076420 - METHOD AND APPARATUS FOR USER EQUIPMENT REGISTRATION
