Release notes for hash.

[SVN r63810]

include/boost/functional/hash/hash.hpp

@@ -30,6 +30,8 @@
 
 namespace boost
 {
+#if !defined(BOOST_HASH_ALLOW_IMPLICIT_CASTS)
+
     // If you get a static assertion here, it's because hash_value
     // isn't declared for your type.
     template <typename T>
@@ -38,6 +40,8 @@ namespace boost
         return 0;
     }
 
+#endif
+
     std::size_t hash_value(bool);
     std::size_t hash_value(char);
     std::size_t hash_value(unsigned char);