Index: property_map.hpp
===================================================================
--- property_map.hpp	(revision 76962)
+++ property_map.hpp	(working copy)
@@ -590,9 +590,60 @@
   };
 
 //=========================================================================
-  // A property map that applies the identity function to integers
-  typedef typed_identity_property_map<std::size_t> identity_property_map;
+  // A property map returns a copy of the key
+  // It is overloaded to do so for any type
+  // but, consequently does not provide correct property_traits 
+  struct identity_property_map 
+  {
+    typedef size_t no_type; // should this be void instead? 
+    typedef no_type key_type; 
+    typedef no_type value_type;
+    typedef no_type reference;
+    typedef boost::readable_property_map_tag category;
 
+    template<typename T>
+    inline T operator[](const T& k) const 
+    {
+      return k;
+    }
+  };
+
+  template<typename T>
+  T get(identity_property_map, const T& k)
+  {
+    return k;
+  }
+  
+  // A property map returns a reference to the key
+  // It is overloaded to do so for any type
+  // but, consequently does not provide correct property_traits 
+  struct identity_ref_property_map 
+  {
+    typedef size_t no_type;// should this be void instead? 
+    typedef no_type key_type; 
+    typedef no_type value_type;
+    typedef no_type reference;
+    typedef boost::lvalue_property_map_tag category;
+
+    template<typename T>
+    inline T& operator[](T& k) const 
+    {
+      return k;
+    }
+  };
+
+  template<typename T>
+  T& get(identity_ref_property_map, T& k)
+  {
+    return k;
+  }
+  
+  template<typename T>
+  void put(identity_ref_property_map, T& k, const T& v)
+  {
+    k = v;
+  }
+  
   //=========================================================================
   // A property map that does not do anything, for
   // when you have to supply a property map, but don't need it.