LibIMS update modifications extending to LibSIP

	  var Contact	vc_contact; 			// value of Contact header

	  var CSeq		vc_cSeq 		:= c_empty_cSeq;	// value of CSeq header

	  var RAck 		vc_rAck 		:= { fieldName := RACK_E, responseNum := 1, seqNumber := 1, method := "INVITE"}; // value of RAck header

	  var template(value) RAck 		vc_rAck 		:= { fieldName := RACK_E, responseNum := 1, seqNumber := 1, method := "INVITE"}; // value of RAck header

	  var HostPort 	vc_reqHostPort 	:= {host:=PX_SIP_SUT_IPADDR, portField:=PX_SIP_SUT_PORT}; // address to send request

	  var Privacy 	vc_privacy;

	  var HistoryInfo_List vc_historyInfoList := {}; // value of history list according to RFC4244