diff --git a/src/ca/cacIO.h b/src/ca/cacIO.h
index bb1b7aedc..29903d0dd 100644
--- a/src/ca/cacIO.h
+++ b/src/ca/cacIO.h
@@ -34,8 +34,8 @@ public:
     virtual void exceptionNotify ( int status, const char *pContext, unsigned type, unsigned long count );
 private:
     cacNotifyIO *pIO;
-    virtual lock ();
-    virtual unlock ();
+    virtual void lock ();
+    virtual void unlock ();
     static osiMutex defaultMutex;
     friend class cacNotifyIO;
 };
diff --git a/src/ca/cacNotify.cpp b/src/ca/cacNotify.cpp
index cbcdfaadf..e4d1ad32e 100644
--- a/src/ca/cacNotify.cpp
+++ b/src/ca/cacNotify.cpp
@@ -27,12 +27,12 @@ cacNotify::~cacNotify ()
     }
 }
 
-cacNotify::lock ()
+void cacNotify::lock ()
 {
     this->defaultMutex.lock ();
 }
 
-cacNotify::unlock ()
+void cacNotify::unlock ()
 {
     this->defaultMutex.unlock ();
 }