Abstract: A method for setting up redirection of contacts coming to a terminal (A) to at least one other communication system (A′), which is advantageously located outside the mobile communication network so that a proposal of and address of a other communication system (A′) is sent by utilizing the data transmission connection set up between the terminal (A) and the first communication system (S) to the terminal (A), whose acceptance of the proposal is followed by the activation of the redirection.

Abstract: The invention relates to a telecommunications system comprising at least a terminal (11) from which a connection can be set up to the Internet (12); and an exchange (14) for routing calls on the basis of information in a register (16). The system further comprises an Internet server (13) comprising means for controlling the instalment of the software required in the terminal (11) for making and receiving VoIP calls and the activation of the application required for making and receiving VoIP calls as a response to the request transmitted from the terminal (11); means for changing call forwarding information in the register (16); means for converting the data flow transmitted from the exchange (14) to the terminal (11) into a mode suitable for the terminal (11).