An apparatus in one example comprises a serving mobile switching center feature server and one or more internet protocol multimedia subsystem components. The serving mobile switching center feature server translates between a call control message originated by or terminated to a mobile telephone and an internet protocol based procedure message. The one or more internet protocol multimedia subsystem components serve to propagate the internet protocol based procedure message. The one or more internet protocol multimedia subsystem components provide packet-switched switching functions to the serving mobile switching center feature server based on the internet protocol based procedure message.