Index: Lib/doctest.py
===================================================================
--- Lib/doctest.py	(revision 80264)
+++ Lib/doctest.py	(working copy)
@@ -216,7 +216,7 @@
                 # get_data() opens files as 'rb', so one must do the equivalent
                 # conversion as universal newlines would do.
                 return file_contents.replace(os.linesep, '\n'), filename
-    return open(filename).read(), filename
+    return open(filename, 'U').read(), filename
 
 # Use sys.stdout encoding for ouput.
 _encoding = getattr(sys.__stdout__, 'encoding', None) or 'utf-8'
Index: Lib/test/test_doctest.py
===================================================================
--- Lib/test/test_doctest.py	(revision 80264)
+++ Lib/test/test_doctest.py	(working copy)
@@ -2329,6 +2329,21 @@
     >>> sys.argv = save_argv
 """
 
+def test_lineendings(): r"""
+Due to the way releases are made on different platforms, we sometimes test
+files on a *nix system with Windows file endings. Unfortunately, that leaves
+some of the test files broken:
+
+    >>> import tempfile
+    >>> fn = tempfile.mktemp()
+    >>> open(fn, 'w').write('Test:\r\n\r\n  >>> x = 1 + 1\r\n\r\nDone.\r\n')
+
+Let's now run it as a doctest:
+
+    >>> doctest.testfile(fn, False)
+    TestResults(failed=0, attempted=1)
+"""
+
 # old_test1, ... used to live in doctest.py, but cluttered it.  Note
 # that these use the deprecated doctest.Tester, so should go away (or
 # be rewritten) someday.