Index: Doc/library/gzip.rst
===================================================================
--- Doc/library/gzip.rst	(revision 68905)
+++ Doc/library/gzip.rst	(working copy)
@@ -46,7 +46,9 @@
    or ``'wb'``, depending on whether the file will be read or written.  The default
    is the mode of *fileobj* if discernible; otherwise, the default is ``'rb'``. If
    not given, the 'b' flag will be added to the mode to ensure the file is opened
-   in binary mode for cross-platform portability.
+   in binary mode for cross-platform portability.  'U' may be included as
+   well when reading.  If present, it is removed from the mode before the gzip
+   file is opened then applied to lines read from the compressed file.
 
    The *compresslevel* argument is an integer from ``1`` to ``9`` controlling the
    level of compression; ``1`` is fastest and produces the least compression, and
Index: Lib/gzip.py
===================================================================
--- Lib/gzip.py	(revision 68905)
+++ Lib/gzip.py	(working copy)
@@ -63,7 +63,9 @@
         depending on whether the file will be read or written.  The default
         is the mode of fileobj if discernible; otherwise, the default is 'rb'.
         Be aware that only the 'rb', 'ab', and 'wb' values should be used
-        for cross-platform portability.
+        for cross-platform portability.  'U' may be included as well when
+        reading.  If present, it is removed from the mode before the gzip
+        file is opened then applied to lines read from the compressed file.
 
         The compresslevel argument is an integer from 1 to 9 controlling the
         level of compression; 1 is fastest and produces the least compression,
@@ -84,8 +86,11 @@
         # that care about that sort of thing
         if mode and 'b' not in mode:
             mode += 'b'
+        mode = mode or 'rb'
+        self._universal = 'U' in mode and 'r' in mode
+        mode = mode.replace('U', '')
         if fileobj is None:
-            fileobj = self.myfileobj = __builtin__.open(filename, mode or 'rb')
+            fileobj = self.myfileobj = __builtin__.open(filename, mode)
         if filename is None:
             if hasattr(fileobj, 'name'): filename = fileobj.name
             else: filename = ''
@@ -236,6 +241,15 @@
                     size = self.extrasize
 
         chunk = self.extrabuf[:size]
+        if self._universal:
+            if (chunk and
+                chunk[-1] == "\r" and
+                len(self.extrabuf) > size and
+                self.extrabuf[size] == "\n"):
+                # We split a CRLF pair - put it back together.
+                size += 1
+                chunk += "\n"
+            chunk = chunk.replace("\r\n", "\n").replace("\r", "\n")
         self.extrabuf = self.extrabuf[size:]
         self.extrasize = self.extrasize - size
 
Index: Lib/test/test_gzip.py
===================================================================
--- Lib/test/test_gzip.py	(revision 68905)
+++ Lib/test/test_gzip.py	(working copy)
@@ -21,7 +21,12 @@
 /* See http://www.winimage.com/zLibDll for Windows */
 """
 
+data3 = """/* zlibmodule.c -- gzip-compatible data compression */\r
+/* See http://www.gzip.org/zlib/\r\r
+/* See http://www.winimage.com/zLibDll for Windows */\r
+"""
 
+
 class TestGzip(unittest.TestCase):
     filename = test_support.TESTFN
 
@@ -31,9 +36,13 @@
     def tearDown(self):
         test_support.unlink(self.filename)
 
+    def _write(self, mode, data):
+        f = gzip.GzipFile(self.filename, mode)
+        f.write(data)
+        return f
 
     def test_write(self):
-        f = gzip.GzipFile(self.filename, 'wb') ; f.write(data1 * 50)
+        f = self._write('wb', data1*50)
 
         # Try flush and fileno.
         f.flush()
@@ -54,7 +63,8 @@
     def test_append(self):
         self.test_write()
         # Append to the previous file
-        f = gzip.GzipFile(self.filename, 'ab') ; f.write(data2 * 15) ; f.close()
+        f = self._write('ab', data2 * 15)
+        f.close()
 
         f = gzip.GzipFile(self.filename, 'rb') ; d = f.read() ; f.close()
         self.assertEqual(d, (data1*50) + (data2*15))
@@ -95,6 +105,20 @@
             line_length = (line_length + 1) % 50
         f.close()
 
+    def test_read_universal(self):
+        self._write('wb', data3)
+        f = gzip.GzipFile(self.filename, 'rbU')
+        udata3 = (data3.replace("\r\n", "\n")
+                       .replace("\r", "\n")
+                       .rstrip("\n")
+                       .split("\n"))
+        n = 0
+        for (fline, dline) in zip(f, udata3):
+            self.assert_(fline == dline + "\n", (fline, dline))
+            n += 1
+        self.assert_(n == len(udata3), (n, len(udata3)))
+        f.close()
+
     def test_readlines(self):
         self.test_write()
         # Try .readlines()