diff -r cb876235f29d Doc/library/zipfile.rst
--- a/Doc/library/zipfile.rst	Tue Feb 12 02:04:27 2013 +0100
+++ b/Doc/library/zipfile.rst	Thu Feb 14 11:25:23 2013 -0500
@@ -130,7 +130,7 @@
 ---------------
 
 
-.. class:: ZipFile(file, mode='r', compression=ZIP_STORED, allowZip64=False)
+.. class:: ZipFile(file, mode='r', compression=ZIP_STORED, allowZip64=True)
 
    Open a ZIP file, where *file* can be either a path to a file (a string) or a
    file-like object.  The *mode* parameter should be ``'r'`` to read an existing
@@ -147,12 +147,9 @@
    :const:`ZIP_BZIP2` or :const:`ZIP_LZMA` is specified but the corresponded module
    (:mod:`zlib`, :mod:`bz2` or :mod:`lzma`) is not available, :exc:`RuntimeError`
    is also raised. The default is :const:`ZIP_STORED`.  If *allowZip64* is
-   ``True`` zipfile will create ZIP files that use the ZIP64 extensions when
-   the zipfile is larger than 2 GB. If it is  false (the default) :mod:`zipfile`
+   ``True`` (the default) zipfile will create ZIP files that use the ZIP64
+   extensions when the zipfile is larger than 2 GB. If it is false :mod:`zipfile`
    will raise an exception when the ZIP file would require ZIP64 extensions.
-   ZIP64 extensions are disabled by default because the default :program:`zip`
-   and :program:`unzip` commands on Unix (the InfoZIP utilities) don't support
-   these extensions.
 
    If the file is created with mode ``'a'`` or ``'w'`` and then
    :meth:`closed <close>` without adding any files to the archive, the appropriate
@@ -373,7 +370,7 @@
 The :class:`PyZipFile` constructor takes the same parameters as the
 :class:`ZipFile` constructor, and one additional parameter, *optimize*.
 
-.. class:: PyZipFile(file, mode='r', compression=ZIP_STORED, allowZip64=False, \
+.. class:: PyZipFile(file, mode='r', compression=ZIP_STORED, allowZip64=True, \
                      optimize=-1)
 
    .. versionadded:: 3.2
diff -r cb876235f29d Lib/test/test_zipfile.py
--- a/Lib/test/test_zipfile.py	Tue Feb 12 02:04:27 2013 +0100
+++ b/Lib/test/test_zipfile.py	Thu Feb 14 11:25:23 2013 -0500
@@ -752,12 +752,12 @@
             fp.write(self.data)
 
     def large_file_exception_test(self, f, compression):
-        with zipfile.ZipFile(f, "w", compression) as zipfp:
+        with zipfile.ZipFile(f, "w", compression, allowZip64=False) as zipfp:
             self.assertRaises(zipfile.LargeZipFile,
                               zipfp.write, TESTFN, "another.name")
 
     def large_file_exception_test2(self, f, compression):
-        with zipfile.ZipFile(f, "w", compression) as zipfp:
+        with zipfile.ZipFile(f, "w", compression, allowZip64=False) as zipfp:
             self.assertRaises(zipfile.LargeZipFile,
                               zipfp.writestr, "another.name", self.data)
         if not isinstance(f, str):
diff -r cb876235f29d Lib/zipfile.py
--- a/Lib/zipfile.py	Tue Feb 12 02:04:27 2013 +0100
+++ b/Lib/zipfile.py	Thu Feb 14 11:25:23 2013 -0500
@@ -869,7 +869,7 @@
 class ZipFile:
     """ Class with methods to open, read, write, close, list zip files.
 
-    z = ZipFile(file, mode="r", compression=ZIP_STORED, allowZip64=False)
+    z = ZipFile(file, mode="r", compression=ZIP_STORED, allowZip64=True)
 
     file: Either the path to the file, or a file-like object.
           If it is a path, the file will be opened and closed by ZipFile.
@@ -885,7 +885,7 @@
     fp = None                   # Set here since __del__ checks it
     _windows_illegal_name_trans_table = None
 
-    def __init__(self, file, mode="r", compression=ZIP_STORED, allowZip64=False):
+    def __init__(self, file, mode="r", compression=ZIP_STORED, allowZip64=True):
         """Open the ZIP file with mode read "r", write "w" or append "a"."""
         if mode not in ("r", "w", "a"):
             raise RuntimeError('ZipFile() requires mode "r", "w", or "a"')
@@ -1554,7 +1554,7 @@
     """Class to create ZIP archives with Python library files and packages."""
 
     def __init__(self, file, mode="r", compression=ZIP_STORED,
-                 allowZip64=False, optimize=-1):
+                 allowZip64=True, optimize=-1):
         ZipFile.__init__(self, file, mode=mode, compression=compression,
                          allowZip64=allowZip64)
         self._optimize = optimize
@@ -1760,7 +1760,7 @@
                             os.path.join(path, nm), os.path.join(zippath, nm))
             # else: ignore
 
-        with ZipFile(args[1], 'w', allowZip64=True) as zf:
+        with ZipFile(args[1], 'w') as zf:
             for src in args[2:]:
                 addToZip(zf, src, os.path.basename(src))