diff --git a/src/ca/nciu.h b/src/ca/nciu.h
index 15888a7e5..fe25b64b9 100644
--- a/src/ca/nciu.h
+++ b/src/ca/nciu.h
@@ -50,6 +50,7 @@
 class cac;
 class netiiu;
 class callbackMutex;
+class cacMutex;
 
 class cacPrivateListOfIO {
 public:
@@ -75,7 +76,7 @@ public:
     void accessRightsNotify ( epicsGuard < callbackMutex > & ) const;
     void disconnect ( netiiu & newiiu );
     bool searchMsg ( class udpiiu & iiu, unsigned & retryNoForThisChannel );
-    void createChannelRequest ( class tcpiiu & iiu );
+    void createChannelRequest ( class tcpiiu & iiu, epicsGuard < cacMutex > & );
     bool identifierEquivelence ( unsigned idToMatch );
     void beaconAnomalyNotify ();
     void serviceShutdownNotify ();
diff --git a/src/ca/virtualCircuit.h b/src/ca/virtualCircuit.h
index 773d5d613..cdb093062 100644
--- a/src/ca/virtualCircuit.h
+++ b/src/ca/virtualCircuit.h
@@ -111,7 +111,7 @@ public:
         ( cacNotify &, epicsGuard < cacMutex > & );
     virtual void show ( unsigned level ) const;
     bool setEchoRequestPending ();
-    void createChannelRequest ( nciu & );
+    void createChannelRequest ( nciu &, epicsGuard < cacMutex > & );
     void requestRecvProcessPostponedFlush ();
     void clearChannelRequest ( epicsGuard < cacMutex > &, 
         ca_uint32_t sid, ca_uint32_t cid );