diff --git a/bindings/python/mapnik_value_converter.hpp b/bindings/python/mapnik_value_converter.hpp
index fb6d6bba8..01b88cb0a 100644
--- a/bindings/python/mapnik_value_converter.hpp
+++ b/bindings/python/mapnik_value_converter.hpp
@@ -54,7 +54,7 @@ namespace boost { namespace python {
             
         PyObject * operator() (mapnik::value_null const& /*s*/) const
         {
-            return NULL;
+            return Py_None;
         }
     };