Telephone set, multimedia terminal and server

The invention concerns a telephone set associated with a multimedia terminal. Said set comprises means for ordering transmission, to a server comprising a database wherein are stored identifiers of telephone sets and identifiers of the multimedia terminals associated with said telephone sets, of a request in the form of a message including an identifier of said first telephone set and an identifier of a second telephone set with which the first set is currently communicating over the phone. The server comprises means for ordering transmission, to a multimedia terminal associated with the first and/or with the second telephone set, of an identifier of another terminal, so as to set up a multimedia communication, through a logical channel different from the telephone communication channel, between said multimedia terminals.