Index: libs/mpi/src/python/datatypes.cpp
===================================================================
--- libs/mpi/src/python/datatypes.cpp	(revision 74484)
+++ libs/mpi/src/python/datatypes.cpp	(working copy)
@@ -17,7 +17,7 @@
 
 void export_datatypes()
 {
-  register_serialized(long(0), &PyInt_Type);
+  register_serialized(long(0), &PyLong_Type);
   register_serialized(false, &PyBool_Type);
   register_serialized(double(0.0), &PyFloat_Type);
 }