A mobile station indicates a need for at least one specific type of Internet Protocol version 6 (IPv6) prefix in a message (73) transmitted to a serving network element. The latter processes this message to determine (74) the indicated IPv6 prefix type and responds with a reply message (75) comprising, at least in part, an IPv6 prefix of a type that is commensurate with the type (or types) indicated by the mobile station in the aforementioned message.