Index: trunk/pstamp/scripts/pstampparse.pl
===================================================================
--- trunk/pstamp/scripts/pstampparse.pl	(revision 26289)
+++ trunk/pstamp/scripts/pstampparse.pl	(revision 27104)
@@ -197,4 +197,5 @@
         # backwards compatability hook
         $data_group = $row->{LABEL};
+        $data_group = "null" if !defined $data_group;
     }