A client device accesses an on-line version of an address book when the client device is connected to a server and alternatively accesses an off-line version of the address book in lieu of the on-line version of the address book when the client device is not connected to the server. The on-line version...http://www.google.de/patents/US20030236842?utm_source=gb-gplus-sharePatent US20030236842 - E-mail address system and method for use between disparate client/server environments
