Index: chrono/duration.hpp
===================================================================
--- chrono/duration.hpp	(revision 69105)
+++ chrono/duration.hpp	(working copy)
@@ -432,8 +432,6 @@
         template <class Rep2>
         BOOST_CHRONO_CONSTEXPR
         explicit duration(const Rep2& r
-#if defined(BOOST_MSVC) && (BOOST_MSVC == 1500)
-#else
         , typename boost::enable_if <
                     mpl::and_ <
                         boost::is_convertible<Rep2, rep>,
@@ -446,8 +444,7 @@
                         >
                     >
                 >::type* = 0
-#endif    
-    )
+		)
                   : rep_(r) { }
         ~duration() {} //= default;
         duration(const duration& rhs) : rep_(rhs.rep_) {} // = default;
@@ -461,19 +458,16 @@
         template <class Rep2, class Period2>
         BOOST_CHRONO_CONSTEXPR
         duration(const duration<Rep2, Period2>& d
-#if defined(BOOST_MSVC) && (BOOST_MSVC == 1500)
-#else
         , typename boost::enable_if <
                     mpl::or_ <
                         treat_as_floating_point<rep>,
                         mpl::and_ <
-                            mpl::bool_ < ratio_divide<Period2, period>::type::den == 1>,
+                            ratio_detail::is_evenly_divisible_by<Period2, period>,
                             mpl::not_ < treat_as_floating_point<Rep2> >
                         >
                     >
                 >::type* = 0
-#endif    
-    )
+        )
             : rep_(chrono::detail::duration_cast<duration<Rep2, Period2>, duration>()(d).count()) {}
 
         // observer
Index: ratio/detail/overflow_helpers.hpp
===================================================================
--- ratio/detail/overflow_helpers.hpp	(revision 69105)
+++ ratio/detail/overflow_helpers.hpp	(working copy)
@@ -300,7 +300,11 @@
              boost::ratio_detail::br_mul<R2::num / gcd_n1_n2, R1::den / gcd_d1_d2>::value
          >::type type;
   };
-  
+
+  template <class R1, class R2>
+  struct is_evenly_divisible_by : public boost::mpl::bool_ < ratio_divide<R1, R2>::type::den == 1 > 
+  {}; 
+
   template <class T>
   struct is_ratio : public boost::false_type 
   {};