The present invention relates to a configuration method and system for providing a configuration parameter, such as a server, gateway or proxy server address(es), to a terminal device. A trigger control information defining trigger events and/or conditions is loaded to the terminal device (11, 21) and a discovery procedure for obtaining the configuration parameter(s) is initiated when at least one of the trigger events and/or conditions is detected. Thereby, a user-friendly automatic configuration of services or server addresses can be provided to a moving mobile terminal.