diff --git a/libs/openzap/src/isdn/Q931api.c b/libs/openzap/src/isdn/Q931api.c
index c2662dbefa..b5e3662316 100644
--- a/libs/openzap/src/isdn/Q931api.c
+++ b/libs/openzap/src/isdn/Q931api.c
@@ -404,6 +404,20 @@ L3INT Q931InitMesResume(Q931mes_Resume * pMes)
 	return 0;
 }
 
+L3INT Q931InitMesRestartAck(Q931mes_RestartAck * pMes)
+{
+	pMes->ProtDisc		= 0x80;
+	pMes->CRV			= 0;		/* CRV to be allocated, might be receive*/
+	pMes->MesType		= Q931mes_RESTART_ACKNOWLEDGE;
+
+	pMes->Size			= Q931GetMesSize((L3UCHAR*)pMes);
+    pMes->ChanID        = 0;        /* Channel Identification               */
+	pMes->Display		= 0;
+	pMes->RestartInd	= 0;
+	pMes->RestartWin	= 0;
+	return 0;
+}
+
 L3INT Q931InitIEBearerCap(Q931ie_BearerCap *pIE)
 {
 	pIE->IEId			= Q931ie_BEARER_CAPABILITY;
diff --git a/libs/openzap/src/isdn/include/Q931.h b/libs/openzap/src/isdn/include/Q931.h
index fe8d3a8e8c..c68f5268a9 100644
--- a/libs/openzap/src/isdn/include/Q931.h
+++ b/libs/openzap/src/isdn/include/Q931.h
@@ -2395,6 +2395,7 @@ void Q931SetIEProc(L3UCHAR iec, L3UCHAR dialect,
 void Q931Initialize();
 void Q931AddDialect(L3UCHAR iDialect, void (*Q931CreateDialectCB)(L3UCHAR iDialect));
 L3INT Q931InitMesSetup(Q931mes_Setup *p);
+L3INT Q931InitMesRestartAck(Q931mes_RestartAck * pMes);
 
 L3INT	Q931CreateCRV(Q931_TrunkInfo_t *pTrunk, L3INT * callIndex);
 L3INT	Q931AllocateCRV(Q931_TrunkInfo_t *pTrunk, L3INT iCRV, L3INT * callIndex);