look at this discussion: http://www.dbforums.com/archive/index.php/t-1100372.html
it looks like we have to use other way, hold the data we want to preseve in an object, because it is possible the class is removed before the instance cleaned, and we can not expect __del__ 100% in handling finalizing process. Pujo -- http://mail.python.org/mailman/listinfo/python-list
