diff --git a/lib/cpp/src/concurrency/Mutex.h b/lib/cpp/src/concurrency/Mutex.h
index 3267c73..4b1c3bf 100644
--- a/lib/cpp/src/concurrency/Mutex.h
+++ b/lib/cpp/src/concurrency/Mutex.h
@@ -138,7 +138,7 @@
 };
 
 
-class RWGuard {
+class RWGuard : boost::noncopyable {
   public:
     RWGuard(const ReadWriteMutex& value, bool write = false)
          : rw_mutex_(value) {