A method for transmitting data from a radio network subsystem to user equipment in a mobile telephone system, a radio network subsystem and user equipment. In the method, the radio network subsystem transmits a dedicated control channel to the user equipment and a dedicated traffic channel of variable data transmission rate to the user equipment. During transmission, the radio network subsystem spreads each channel with a spreading code, and the spreading code used to spread the traffic channel is changed according to the required data transmission rate. According to the invention, each control channel frame indicates the spreading code with which the corresponding traffic channel is spread when transmitted.