diff --git a/lib_acl_cpp/include/acl_cpp/stdlib/mbox.hpp b/lib_acl_cpp/include/acl_cpp/stdlib/mbox.hpp
index bbff97df5..b2596e46d 100644
--- a/lib_acl_cpp/include/acl_cpp/stdlib/mbox.hpp
+++ b/lib_acl_cpp/include/acl_cpp/stdlib/mbox.hpp
@@ -48,7 +48,7 @@ size_t mbox_nread(void*);
  */
 
 template<typename T>
-class mbox
+class mbox : public noncopyable
 {
 public:
 	mbox(void)