Handheld electronic device including automatic mobile phone number management, and associated method

A method of updating information included in a handheld device user's contact entry included in a global address list wherein the device stores information of a first type, such as a mobile phone, SMS or MMS number or a PIN. The method includes determining whether the information of a first type has been modified from a first stored piece of information to a second stored piece of information, and generating a message including the second stored piece of information and sending the message to a computer system of the organization if it is determined that the information of a first type has been modified. The computer system stores the second stored piece of information in response to receipt of the message by the computer system for subsequent access by a requesting party. Also provided is an improved handheld electronic device having one or more routines adapted to implement the method.