Abstract: The invocation of an intelligent network service in a call handler for calls being routed to mobile stations in a mobile communication network is done in such a way that if a call being handled is a call to be routed to a mobile station, and if it is determined that at least one intelligent network identifier is activated for that mobile station a further comparison of a stored condition parameter of the mobile station with a current value of that mobile station's condition parameter is performed, and where the decision regarding the invocation of an intelligent network service depends on the outcome of such a comparison.

Abstract: When a mobile station (MS) roams from a first telecommunication network (HPLMN) to a second telecommunication network (VPLMN) some of the features of the services to which the subscriber has subscribed to in the first telecommunication network (HPLMN) are differently implemented in the second network (VPLMN). According to the invention, the subscriber data and/or service data of services or of features of these services which are not supported in the second network (VPLMN) are converted by a conversion means (CM) of a service providing means (ASPM) into a format for a service which is supported in the second network (MSC/VLR′). Preferably, a dynamic updating and conversion can be performed such that the respective data is converted whenever it changes. Functionalities provided by a specific service supported differently in the second network will be provided by a service or a feature of a service which is available in the second network.