Message server, message system, and method of management of presence information as well as program for implementing presence information management

摘要

A method and system for management of a presence information by a message server. A presence information of at least one member listed on each communication group member list belonging to each user is notified. A presence information is renewed, which belongs to a terminal of a user as sender who sends a message to the message server. The presence information is automatically renewed in response to at least one of a first type event that the message server has received at least one of the message and any other communication from the user as sender, and a second type event that an effective time period for the presence information has expired.