Abstract: A communications service provision support system supports multiple different types of services during a service session. The system when in use comprises a session manager which performs functions generic to each of the multiple different types of services during service sessions. For each of the multiple types of services, the session manager is arranged during a service session to generate event messages indicating at least one discrete change which has just occurred in the session-related status of individual users of the system without any historical data, and to transmit the event messages to an event handler for processing.

Abstract: A data processing apparatus for providing an object-oriented execution environment, such as a virtual machine operable for first and second versions of the same class is disclosed. The data processing apparatus communicates with first and second services respectively operative for first and second versions of the same class. However, the first service is allowed to communicate only with a first version execution environment, and the second service is allowed to communicate only with a second version execution environment. The data processing apparatus is configured so that different versions of a class can share data or information between them.