--- pyparsing_py3.py.orig	2013-04-03 01:28:01.927400414 +0200
+++ pyparsing_py3.py	2013-04-03 01:28:23.903443448 +0200
@@ -891,7 +891,7 @@
                 ParserElement._exprArgCache[ lookup ] = (value[0],value[1].copy())
                 return value
             except ParseBaseException as pe:
-                exc.__traceback__ = None
+                pe.__traceback__ = None
                 ParserElement._exprArgCache[ lookup ] = pe
                 raise