the invention consists of a method and a system arranged to transmit an identity of a user from a terminal to a database adapted to permanently store information of said user , in a mobile telecommunications network , comprising : inputting means adapted to allow said user to input said identity at said terminal , whereby said identity is modified on a permanent basis by said user ; transmitting means adapted to transmit in the form of a message , said identity from said terminal to said database ; storing means adapted upon reception of said message to store said identity at said database .