A distribution server for geographically targeted message distribution to a client is used for providing an application service, in particular a vehicular traffic related application service, such as a Cooperative Intelligent Transport System (C-ITS) service. An interworking device connects, e.g., via a cellular network connection, to the distribution server. Further, the interworking device connects via an ad-hoc network connection to the client. On behalf of the client, the interworking device performs registration for the application service at the distribution server. On the basis of the registration, the interworking device forwards at least one message of the application service between the distribution server and the client.