diff --git a/include/boost/mpl/arg.hpp b/include/boost/mpl/arg.hpp
index 7690f6d..a322f8b 100644
--- a/include/boost/mpl/arg.hpp
+++ b/include/boost/mpl/arg.hpp
@@ -25,6 +25,7 @@
 #   include "boost/mpl/arg_fwd.hpp"
 #   include "boost/mpl/void.hpp"
 #   include "boost/mpl/aux_/arity_spec.hpp"
+#   include "boost/mpl/aux_/arg_typedef.hpp"
 #   include "boost/static_assert.hpp"
 #endif
 
@@ -95,9 +96,7 @@ template<> struct arg<i>
 {
     BOOST_STATIC_CONSTANT(int, value = i);
     typedef arg<BOOST_PP_INC(i)> next;
-#if defined(BOOST_MPL_NO_FULL_LAMBDA_SUPPORT)
-    typedef void_ tag;
-#endif
+    BOOST_MPL_AUX_ARG_TYPEDEF(void_, tag)
 
     template<
           AUX_ARG_N_DEFAULT_PARAMS(typename U, void_)
@@ -118,9 +117,7 @@ template<> struct arg<i>
 template<> struct arg<-1>
 {
     BOOST_STATIC_CONSTANT(int, value = -1);
-#if defined(BOOST_MPL_NO_FULL_LAMBDA_SUPPORT)
-    typedef void_ tag;
-#endif
+    BOOST_MPL_AUX_ARG_TYPEDEF(void_, tag)
 
     template<
           AUX_ARG_N_DEFAULT_PARAMS(typename U, void_)
diff --git a/include/boost/mpl/aux_/arg_typedef.hpp b/include/boost/mpl/aux_/arg_typedef.hpp
new file mode 100644
index 0000000..19b6bc0
--- /dev/null
+++ b/include/boost/mpl/aux_/arg_typedef.hpp
@@ -0,0 +1,28 @@
+//-----------------------------------------------------------------------------
+// boost mpl/aux_/arg_typedef.hpp header file
+// See http://www.boost.org for updates, documentation, and revision history.
+//-----------------------------------------------------------------------------
+//
+// Copyright (c) 2001-02
+// Aleksey Gurtovoy
+//
+// Permission to use, copy, modify, distribute and sell this software
+// and its documentation for any purpose is hereby granted without fee, 
+// provided that the above copyright notice appears in all copies and 
+// that both the copyright notice and this permission notice appear in 
+// supporting documentation. No representations are made about the 
+// suitability of this software for any purpose. It is provided "as is" 
+// without express or implied warranty.
+
+#ifndef BOOST_MPL_AUX_ARG_TYPEDEF_HPP_INCLUDED
+#define BOOST_MPL_AUX_ARG_TYPEDEF_HPP_INCLUDED
+
+#include "boost/mpl/aux_/config/lambda.hpp"
+
+#if defined(BOOST_MPL_NO_FULL_LAMBDA_SUPPORT)
+#   define BOOST_MPL_AUX_ARG_TYPEDEF(T, name) typedef T name;
+#else
+#   define BOOST_MPL_AUX_ARG_TYPEDEF(T, name) /**/
+#endif
+
+#endif // BOOST_MPL_AUX_ARG_TYPEDEF_HPP_INCLUDED