1. A method, comprising: detecting a change in a state of a connection between a terminal device and a gateway node of a packet data based mobile communication network, wherein the mobile communication network comprises one or more terminal devices; deriving, at the gateway node, roaming status information on the terminal device; and sending a request for service policy for a subscriber of said terminal device from the gateway node to a session controller of the mobile communication network, said request comprising the roaming status information for service control in the mobile communication network, wherein said service policy indicates which subscriber data services are allowed for said subscriber and further indicating rules for allowed subscriber data services, said rules indicating at least one of different charges and different quality of services for the allowed subscriber data services of said terminal device when roaming, compared to when at home.