[Python.NET] no module name _sre

I have been using PythonWin2.4.1 (#65, Jun 20 2005, 17:01:55) [MSC v.1310 32 bit (Intel)] on win32 for nearly one year. Yesterday I added Python for .Net (Python 2.3.4 #53 May 25 2004). Now some of my old code (originally written some years ago on a Unix platform and which worked unmodified with PythonWin) does not work. Here are two illustrations: 1. No module named _sre 2. from os.path import (curdir, ^ SyntaxError: invalid syntax Please advise.