diff --git a/boost/mpl/aux_/na.hpp b/boost/mpl/aux_/na.hpp
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+++ b/boost/mpl/aux_/na.hpp
@@ -0,0 +1,95 @@
+
+#ifndef BOOST_MPL_AUX_NA_HPP_INCLUDED
+#define BOOST_MPL_AUX_NA_HPP_INCLUDED
+
+// Copyright Aleksey Gurtovoy 2001-2004
+//
+// Distributed under the Boost Software License, Version 1.0. 
+// (See accompanying file LICENSE_1_0.txt or copy at 
+// http://www.boost.org/LICENSE_1_0.txt)
+//
+// See http://www.boost.org/libs/mpl for documentation.
+
+// $Id: na.hpp 49267 2008-10-11 06:19:02Z agurtovoy $
+// $Date: 2008-10-10 23:19:02 -0700 (Fri, 10 Oct 2008) $
+// $Revision: 49267 $
+
+#include <boost/mpl/bool.hpp>
+#include <boost/mpl/aux_/na_fwd.hpp>
+#include <boost/mpl/aux_/config/msvc.hpp>
+#include <boost/mpl/aux_/config/ctps.hpp>
+
+namespace ndnboost { namespace mpl {
+
+template< typename T >
+struct is_na
+    : false_
+{
+#if BOOST_WORKAROUND(BOOST_MSVC, < 1300)
+    using false_::value;
+#endif
+};
+
+template<>
+struct is_na<na>
+    : true_
+{
+#if BOOST_WORKAROUND(BOOST_MSVC, < 1300)
+    using true_::value;
+#endif
+};
+
+template< typename T >
+struct is_not_na
+    : true_
+{
+#if BOOST_WORKAROUND(BOOST_MSVC, < 1300)
+    using true_::value;
+#endif
+};
+
+template<>
+struct is_not_na<na>
+    : false_
+{
+#if BOOST_WORKAROUND(BOOST_MSVC, < 1300)
+    using false_::value;
+#endif
+};
+
+#if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
+template< typename T, typename U > struct if_na
+{
+    typedef T type;
+};
+
+template< typename U > struct if_na<na,U>
+{
+    typedef U type;
+};
+#else
+template< typename T > struct if_na_impl
+{
+    template< typename U > struct apply
+    {
+        typedef T type;
+    };
+};
+
+template<> struct if_na_impl<na>
+{
+    template< typename U > struct apply
+    {
+        typedef U type;
+    };
+};
+
+template< typename T, typename U > struct if_na
+    : if_na_impl<T>::template apply<U>
+{
+};
+#endif
+
+}}
+
+#endif // BOOST_MPL_AUX_NA_HPP_INCLUDED