--- src/pl/plpgsql/src/pl_comp.c.orig	Wed Oct  4 03:30:13 2006
+++ src/pl/plpgsql/src/pl_comp.c	Wed Jan 31 19:47:56 2007
@@ -1471,6 +1471,7 @@
 				var->value = 0;
 				var->isnull = true;
 				var->freeval = false;
+				var->notnull = dtype->typnotnull;

 				plpgsql_adddatum((PLpgSQL_datum *) var);
 				if (add2namespace)
@@ -1768,6 +1769,7 @@
 	typ->typioparam = getTypeIOParam(typeTup);
 	fmgr_info(typeStruct->typinput, &(typ->typinput));
 	typ->atttypmod = typmod;
+	typ->typnotnull = typeStruct->typnotnull;

 	return typ;
 }