Special call fee charging method

A special call fee charging method, comprising the steps of:

• causing an exchange device to receive a call origination signal from a call origination subscriber terminal unit;
• causing the exchange device to inquire of a special charging server whether or not the call origination subscriber terminal unit is a specially charged subscriber terminal unit;
• causing the special charging server to reply to the exchange device whether or not the call origination subscriber terminal unit is a specially charged subscriber terminal unit;
• if the call origination terminal unit is a specially charged call terminal unit, causing the exchange device to notify a general charging server that the call origination subscriber terminal unit is charged a special call fee;
• causing the exchange device to inquire of the special charging server about a charging period;
• causing the special charging server to notify the exchange device of the charging period;
• and
• causing the exchange device to send a charging request to the general charging server whenever the charging period elapses in a talk.