1. Call management procedures for use in a Long Term Evolution/System Architecture Evolution (LTE/SAE) system, said system including a Serving GPRS Support Node (SGSN) and an Evolved Universal Terrestrial Radio Access Network (EUTRAN), said procedures comprising: a Mobility Management Entity (MME) arranged to provide Non-Access Stratum (NAS) signaling between the SGSN and the EUTRAN according to General Packet Radio Service (GPRS) Mobility Management (MM) procedures; wherein the MME is arranged to provide NAS signaling according to GPRS Session Management (SM) procedures; wherein the SM for LTE/SAE includes a packet data protocol (PDP) context in order to establish, modify or tear down PDP sessions; and, wherein the procedures establish, modify or tear down PDP sessions in the same manner as that in GMM/SM, as performed from the MME or a User Equipment (UE).