A method and system for delivering messages to a user in a computerized communication system, such as an instant messaging (IM) system. When a computer system receives a registration message indicating that a user is currently active at a given station, the computer system responsively sets the given client station as a target station for messages directed to the user. If no user activity is detected at the given client station for a predefined period of time, however, the computer system then automatically sets a new client station as the target station for subsequent messages directed to the user.