diff --git a/include/boost/shared_array.hpp b/include/boost/shared_array.hpp
index eb69c8e..3b82f35 100644
--- a/include/boost/shared_array.hpp
+++ b/include/boost/shared_array.hpp
@@ -103,7 +103,23 @@ public:
         return px != 0;
     }
 
-#elif defined(__MWERKS__) && BOOST_WORKAROUND(__MWERKS__, BOOST_TESTED_AT(0x3003))
+#elif defined( _MANAGED )
+
+    static void unspecified_bool( this_type*** )
+    {
+    }
+
+    typedef void (*unspecified_bool_type)( this_type*** );
+
+    operator unspecified_bool_type() const // never throws
+    {
+        return px == 0? 0: unspecified_bool;
+    }
+
+#elif \
+    ( defined(__MWERKS__) && BOOST_WORKAROUND(__MWERKS__, < 0x3200) ) || \
+    ( defined(__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__ < 304) )
+
     typedef T * (this_type::*unspecified_bool_type)() const;
     
     operator unspecified_bool_type() const // never throws