diff --git a/src/pl/plpython/plpython.c b/src/pl/plpython/plpython.c
index 40a57a69dc1..329387b428b 100644
--- a/src/pl/plpython/plpython.c
+++ b/src/pl/plpython/plpython.c
@@ -29,7 +29,7 @@
  * MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  *
  * IDENTIFICATION
- *	$PostgreSQL: pgsql/src/pl/plpython/plpython.c,v 1.66.2.1 2005/12/29 21:47:40 neilc Exp $
+ *	$PostgreSQL: pgsql/src/pl/plpython/plpython.c,v 1.66.2.2 2006/01/10 00:33:30 neilc Exp $
  *
  *********************************************************************
  */
@@ -903,6 +903,7 @@ PLy_function_build_args(FunctionCallInfo fcinfo, PLyProcedure * proc)
 			 * FIXME -- error check this
 			 */
 			PyList_SetItem(args, i, arg);
+			arg = NULL;
 		}
 	}
 	PG_CATCH();