Index: Lib/doctest.py
===================================================================
--- Lib/doctest.py	(revision 59907)
+++ Lib/doctest.py	(working copy)
@@ -207,6 +207,7 @@
         raise TypeError("Expected a module, string, or None")
 
 def _load_testfile(filename, package, module_relative):
+    file_contents = None
     if module_relative:
         package = _normalize_module(package, 3)
         filename = _module_relative_path(package, filename)
@@ -214,9 +215,18 @@
             if hasattr(package.__loader__, 'get_data'):
                 file_contents = package.__loader__.get_data(filename)
                 # 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
+                # conversion as universal newlines would do -- see below.
+    if file_contents is None:
+        f = open(filename, 'rU') # we hope universal newline support is enabled
+        file_contents = f.read()
+        if hasattr(f, 'newlines'):
+            # Universal newlines are enabled, we're OK
+            return file_contents, filename
+    # If we get here, we need to do the universal newline conversion ourselves;
+    # we have two possible cases and we need to do them in the right order
+    for linesep in ('\r\n', '\r'):
+        file_contents = file_contents.replace(linesep, '\n')
+    return file_contents, filename
 
 def _indent(s, indent=4):
     """
Index: Lib/test/test_doctest.py
===================================================================
--- Lib/test/test_doctest.py	(revision 59907)
+++ Lib/test/test_doctest.py	(working copy)
@@ -2279,6 +2279,16 @@
     >>> doctest.testfile('test_doctest4.txt', encoding='utf-8')
     TestResults(failed=0, attempted=4)
     >>> doctest.master = None  # Reset master.
+
+We use a helper script to test for correct newline handling in
+the _load_testfile function:
+
+    >>> from test import doctest_testfile
+    >>> doctest_testfile.run()
+    *** DocTestRunner.merge: 'doctest_testfile.txt' in both testers; summing outcomes.
+    *** DocTestRunner.merge: 'doctest_testfile.txt' in both testers; summing outcomes.
+    *** DocTestRunner.merge: 'doctest_testfile.txt' in both testers; summing outcomes.
+    >>> doctest.master = None  # Reset master.
 """
 
 # old_test1, ... used to live in doctest.py, but cluttered it.  Note
Index: Lib/test/doctest_testfile.py
===================================================================
--- Lib/test/doctest_testfile.py	(revision 0)
+++ Lib/test/doctest_testfile.py	(revision 0)
@@ -0,0 +1,64 @@
+"""
+Test script to exercise all code paths in
+_load_testfile in doctest.py
+
+To be called from test_doctest.py
+"""
+
+# Assumes that it is run from a directory which looks like
+# a top-level package to the Python importer (normally
+# the test directory of the Python installation)
+
+import sys
+import os
+import os.path
+import doctest
+from test import test_importhooks
+
+curdir = os.getcwd()
+curname = "doctest_testfile"
+rootpath, pkgname = os.path.split(curdir)
+hookpkgname = "hooktestpackage"
+txtfile = curname + ".txt"
+
+# Need helper classes for the package loader test, code cribbed
+# shamelessly from test_importhooks
+class PackageLoaderTestImporter(test_importhooks.TestImporter):
+    def _get__path__(self):
+        return curdir
+    def get_data(self, path):
+        if os.path.isfile(path):
+            return open(path, 'rb').read()
+        raise IOError, "File %s not found." % path
+
+class InstallHook:
+    def __init__(self, pkgname):
+        self.pkgname = pkgname
+        self.metapath = sys.meta_path[:]
+        sys.path_importer_cache.clear()
+        self.importer = PackageLoaderTestImporter()
+        sys.meta_path.append(self.importer)
+    def remove(self):
+        sys.meta_path[:] = self.metapath
+        sys.path_importer_cache.clear()
+        del sys.modules[self.pkgname]
+        del self.importer
+
+def run():
+    # First test the default (module_relative=True, no package)
+    doctest.testfile(txtfile)
+    
+    # Now try a non-None package, but no __loader___
+    doctest.testfile(txtfile, package=pkgname)
+    
+    # Now try a package with a __loader___.get_data method
+    hook = InstallHook(hookpkgname)
+    doctest.testfile(txtfile, package=hookpkgname)
+    hook.remove()
+    del hook
+    
+    # Now try loading with module_relative=False
+    doctest.testfile(os.path.join(curdir, txtfile), module_relative=False)
+
+if __name__ == '__main__':
+    run()
Index: Lib/test/doctest_testfile.txt
===================================================================
--- Lib/test/doctest_testfile.txt	(revision 0)
+++ Lib/test/doctest_testfile.txt	(revision 0)
@@ -0,0 +1,11 @@
+This doctest verifies universal newline support; each command
+line has a different platform's end of line convention.
+
+(NOTE: Editing this file with a text editor could clobber the
+end of line characters!)
+
+  >>> print "Unix newline OK."
+  Unix newline OK.
+  >>> print "Windows newline OK."
+  Windows newline OK.
+  >>> print "MAC newline OK."
  MAC newline OK.
\ No newline at end of file