diff -r 71beb1eb6810 Lib/test/test_codecs.py
--- a/Lib/test/test_codecs.py	Fri Oct 01 16:49:24 2010 +0200
+++ b/Lib/test/test_codecs.py	Fri Oct 01 12:20:30 2010 -0400
@@ -1230,6 +1230,17 @@
         f = self.reader(self.stream)
         self.assertEquals(f.readlines(), ['\ud55c\n', '\uae00'])
 
+    def test_readlines_unicode_separators(self):
+        """Tests that the readlines() method splits on Unicode line separator
+        (U+2028) and paragraph separator (U+2029) characters in addition to
+        other line endings (issue 6664).
+
+        """
+        teststring = 'line 1\nline 2\u2029line 3'.encode('utf-8')
+        f = codecs.getreader('utf-8')(io.BytesIO(teststring))
+        self.assertEquals(['line 1\n', 'line 2\u2029', 'line 3'],
+                          f.readlines())
+
 class EncodedFileTest(unittest.TestCase):
 
     def test_basic(self):
diff -r 71beb1eb6810 Lib/test/test_io.py
--- a/Lib/test/test_io.py	Fri Oct 01 16:49:24 2010 +0200
+++ b/Lib/test/test_io.py	Fri Oct 01 12:20:30 2010 -0400
@@ -2093,6 +2093,17 @@
         txt.seek(0)
         self.assertEqual(txt.readlines(5), ["AA\n", "BB\n"])
 
+    def test_readlines_unicode_separators(self):
+        """Tests that the readlines() method splits on Unicode line separator
+        (U+2028) and paragraph separator (U+2029) characters in addition to
+        other line endings (issue 6664).
+
+        """
+        teststring = 'line 1\nline 2\u2029line 3'.encode('utf-8')
+        txt = self.TextIOWrapper(self.BytesIO(teststring))
+        self.assertEquals(['line 1\n', 'line 2\u2029', 'line 3'],
+                          txt.readlines())
+
     # read in amounts equal to TextIOWrapper._CHUNK_SIZE which is 128.
     def test_read_by_chunk(self):
         # make sure "\r\n" straddles 128 char boundary.