[1.1.X] Repeat the setUp/tearDown changes made in r11699 for the tests

converted in r11694. This allows the dateformat tests to pass
on Windows. 


git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.1.X@11702 bcc190cf-cafb-0310-a4f2-bffc1f526a37