diff --git a/Doc/library/mailbox.rst b/Doc/library/mailbox.rst
index f76c97a..6db68ee 100644
--- a/Doc/library/mailbox.rst
+++ b/Doc/library/mailbox.rst
@@ -1501,133 +1501,6 @@
    instance attempts to read a corrupted :file:`.mh_sequences` file.
 
 
-.. _mailbox-deprecated:
-
-Deprecated classes and methods
-------------------------------
-
-Older versions of the :mod:`mailbox` module do not support modification of
-mailboxes, such as adding or removing message, and do not provide classes to
-represent format-specific message properties. For backward compatibility, the
-older mailbox classes are still available, but the newer classes should be used
-in preference to them.
-
-Older mailbox objects support only iteration and provide a single public method:
-
-
-.. method:: oldmailbox.next()
-
-   Return the next message in the mailbox, created with the optional *factory*
-   argument passed into the mailbox object's constructor. By default this is an
-   :class:`rfc822.Message` object (see the :mod:`rfc822` module).  Depending on the
-   mailbox implementation the *fp* attribute of this object may be a true file
-   object or a class instance simulating a file object, taking care of things like
-   message boundaries if multiple mail messages are contained in a single file,
-   etc.  If no more messages are available, this method returns ``None``.
-
-Most of the older mailbox classes have names that differ from the current
-mailbox class names, except for :class:`Maildir`. For this reason, the new
-:class:`Maildir` class defines a :meth:`next` method and its constructor differs
-slightly from those of the other new mailbox classes.
-
-The older mailbox classes whose names are not the same as their newer
-counterparts are as follows:
-
-
-.. class:: UnixMailbox(fp[, factory])
-
-   Access to a classic Unix-style mailbox, where all messages are contained in a
-   single file and separated by ``From`` (a.k.a. ``From_``) lines.  The file object
-   *fp* points to the mailbox file.  The optional *factory* parameter is a callable
-   that should create new message objects.  *factory* is called with one argument,
-   *fp* by the :meth:`next` method of the mailbox object.  The default is the
-   :class:`rfc822.Message` class (see the :mod:`rfc822` module -- and the note
-   below).
-
-   .. note::
-
-      For reasons of this module's internal implementation, you will probably want to
-      open the *fp* object in binary mode.  This is especially important on Windows.
-
-   For maximum portability, messages in a Unix-style mailbox are separated by any
-   line that begins exactly with the string ``'From '`` (note the trailing space)
-   if preceded by exactly two newlines. Because of the wide-range of variations in
-   practice, nothing else on the ``From_`` line should be considered.  However, the
-   current implementation doesn't check for the leading two newlines.  This is
-   usually fine for most applications.
-
-   The :class:`UnixMailbox` class implements a more strict version of ``From_``
-   line checking, using a regular expression that usually correctly matched
-   ``From_`` delimiters.  It considers delimiter line to be separated by ``From
-   name time`` lines.  For maximum portability, use the
-   :class:`PortableUnixMailbox` class instead.  This class is identical to
-   :class:`UnixMailbox` except that individual messages are separated by only
-   ``From`` lines.
-
-
-.. class:: PortableUnixMailbox(fp[, factory])
-
-   A less-strict version of :class:`UnixMailbox`, which considers only the ``From``
-   at the beginning of the line separating messages.  The "*name* *time*" portion
-   of the From line is ignored, to protect against some variations that are
-   observed in practice.  This works since lines in the message which begin with
-   ``'From '`` are quoted by mail handling software at delivery-time.
-
-
-.. class:: MmdfMailbox(fp[, factory])
-
-   Access an MMDF-style mailbox, where all messages are contained in a single file
-   and separated by lines consisting of 4 control-A characters.  The file object
-   *fp* points to the mailbox file. Optional *factory* is as with the
-   :class:`UnixMailbox` class.
-
-
-.. class:: MHMailbox(dirname[, factory])
-
-   Access an MH mailbox, a directory with each message in a separate file with a
-   numeric name. The name of the mailbox directory is passed in *dirname*.
-   *factory* is as with the :class:`UnixMailbox` class.
-
-
-.. class:: BabylMailbox(fp[, factory])
-
-   Access a Babyl mailbox, which is similar to an MMDF mailbox.  In Babyl format,
-   each message has two sets of headers, the *original* headers and the *visible*
-   headers.  The original headers appear before a line containing only ``'*** EOOH
-   ***'`` (End-Of-Original-Headers) and the visible headers appear after the
-   ``EOOH`` line.  Babyl-compliant mail readers will show you only the visible
-   headers, and :class:`BabylMailbox` objects will return messages containing only
-   the visible headers.  You'll have to do your own parsing of the mailbox file to
-   get at the original headers.  Mail messages start with the EOOH line and end
-   with a line containing only ``'\037\014'``.  *factory* is as with the
-   :class:`UnixMailbox` class.
-
-If you wish to use the older mailbox classes with the :mod:`email` module rather
-than the deprecated :mod:`rfc822` module, you can do so as follows::
-
-   import email
-   import email.Errors
-   import mailbox
-
-   def msgfactory(fp):
-       try:
-           return email.message_from_file(fp)
-       except email.Errors.MessageParseError:
-           # Don't return None since that will
-           # stop the mailbox iterator
-           return ''
-
-   mbox = mailbox.UnixMailbox(fp, msgfactory)
-
-Alternatively, if you know your mailbox contains only well-formed MIME messages,
-you can simplify this to::
-
-   import email
-   import mailbox
-
-   mbox = mailbox.UnixMailbox(fp, email.message_from_file)
-
-
 .. _mailbox-examples:
 
 Examples
diff --git a/Lib/mailbox.py b/Lib/mailbox.py
index 3ee9cbe..a12f478 100755
--- a/Lib/mailbox.py
+++ b/Lib/mailbox.py
@@ -1925,184 +1925,6 @@
     _sync_flush(f)
     f.close()
 
-## Start: classes from the original module (for backward compatibility).
-
-# Note that the Maildir class, whose name is unchanged, itself offers a next()
-# method for backward compatibility.
-
-class _Mailbox:
-
-    def __init__(self, fp, factory=rfc822.Message):
-        self.fp = fp
-        self.seekp = 0
-        self.factory = factory
-
-    def __iter__(self):
-        return iter(self.next, None)
-
-    def next(self):
-        while 1:
-            self.fp.seek(self.seekp)
-            try:
-                self._search_start()
-            except EOFError:
-                self.seekp = self.fp.tell()
-                return None
-            start = self.fp.tell()
-            self._search_end()
-            self.seekp = stop = self.fp.tell()
-            if start != stop:
-                break
-        return self.factory(_PartialFile(self.fp, start, stop))
-
-# Recommended to use PortableUnixMailbox instead!
-class UnixMailbox(_Mailbox):
-
-    def _search_start(self):
-        while 1:
-            pos = self.fp.tell()
-            line = self.fp.readline()
-            if not line:
-                raise EOFError
-            if line[:5] == 'From ' and self._isrealfromline(line):
-                self.fp.seek(pos)
-                return
-
-    def _search_end(self):
-        self.fp.readline()      # Throw away header line
-        while 1:
-            pos = self.fp.tell()
-            line = self.fp.readline()
-            if not line:
-                return
-            if line[:5] == 'From ' and self._isrealfromline(line):
-                self.fp.seek(pos)
-                return
-
-    # An overridable mechanism to test for From-line-ness.  You can either
-    # specify a different regular expression or define a whole new
-    # _isrealfromline() method.  Note that this only gets called for lines
-    # starting with the 5 characters "From ".
-    #
-    # BAW: According to
-    #http://home.netscape.com/eng/mozilla/2.0/relnotes/demo/content-length.html
-    # the only portable, reliable way to find message delimiters in a BSD (i.e
-    # Unix mailbox) style folder is to search for "\n\nFrom .*\n", or at the
-    # beginning of the file, "^From .*\n".  While _fromlinepattern below seems
-    # like a good idea, in practice, there are too many variations for more
-    # strict parsing of the line to be completely accurate.
-    #
-    # _strict_isrealfromline() is the old version which tries to do stricter
-    # parsing of the From_ line.  _portable_isrealfromline() simply returns
-    # true, since it's never called if the line doesn't already start with
-    # "From ".
-    #
-    # This algorithm, and the way it interacts with _search_start() and
-    # _search_end() may not be completely correct, because it doesn't check
-    # that the two characters preceding "From " are \n\n or the beginning of
-    # the file.  Fixing this would require a more extensive rewrite than is
-    # necessary.  For convenience, we've added a PortableUnixMailbox class
-    # which does no checking of the format of the 'From' line.
-
-    _fromlinepattern = (r"From \s*[^\s]+\s+\w\w\w\s+\w\w\w\s+\d?\d\s+"
-                        r"\d?\d:\d\d(:\d\d)?(\s+[^\s]+)?\s+\d\d\d\d\s*"
-                        r"[^\s]*\s*"
-                        "$")
-    _regexp = None
-
-    def _strict_isrealfromline(self, line):
-        if not self._regexp:
-            import re
-            self._regexp = re.compile(self._fromlinepattern)
-        return self._regexp.match(line)
-
-    def _portable_isrealfromline(self, line):
-        return True
-
-    _isrealfromline = _strict_isrealfromline
-
-
-class PortableUnixMailbox(UnixMailbox):
-    _isrealfromline = UnixMailbox._portable_isrealfromline
-
-
-class MmdfMailbox(_Mailbox):
-
-    def _search_start(self):
-        while 1:
-            line = self.fp.readline()
-            if not line:
-                raise EOFError
-            if line[:5] == '\001\001\001\001\n':
-                return
-
-    def _search_end(self):
-        while 1:
-            pos = self.fp.tell()
-            line = self.fp.readline()
-            if not line:
-                return
-            if line == '\001\001\001\001\n':
-                self.fp.seek(pos)
-                return
-
-
-class MHMailbox:
-
-    def __init__(self, dirname, factory=rfc822.Message):
-        import re
-        pat = re.compile('^[1-9][0-9]*$')
-        self.dirname = dirname
-        # the three following lines could be combined into:
-        # list = map(long, filter(pat.match, os.listdir(self.dirname)))
-        list = os.listdir(self.dirname)
-        list = filter(pat.match, list)
-        list = map(int, list)
-        list.sort()
-        # This only works in Python 1.6 or later;
-        # before that str() added 'L':
-        self.boxes = map(str, list)
-        self.boxes.reverse()
-        self.factory = factory
-
-    def __iter__(self):
-        return iter(self.next, None)
-
-    def next(self):
-        if not self.boxes:
-            return None
-        fn = self.boxes.pop()
-        fp = open(os.path.join(self.dirname, fn), newline='')
-        msg = self.factory(fp)
-        try:
-            msg._mh_msgno = fn
-        except (AttributeError, TypeError):
-            pass
-        return msg
-
-
-class BabylMailbox(_Mailbox):
-
-    def _search_start(self):
-        while 1:
-            line = self.fp.readline()
-            if not line:
-                raise EOFError
-            if line == '*** EOOH ***\n':
-                return
-
-    def _search_end(self):
-        while 1:
-            pos = self.fp.tell()
-            line = self.fp.readline()
-            if not line:
-                return
-            if line == '\037\014\n' or line == '\037':
-                self.fp.seek(pos)
-                return
-
-## End: classes from the original module (for backward compatibility).
-
 
 class Error(Exception):
     """Raised for module-specific errors."""
diff --git a/Lib/test/test_mailbox.py b/Lib/test/test_mailbox.py
index bc77621..e14516d 100644
--- a/Lib/test/test_mailbox.py
+++ b/Lib/test/test_mailbox.py
@@ -1768,20 +1768,7 @@
         self.assert_(self.mbox.next() is None)
         self.assert_(self.mbox.next() is None)
 
-    def test_unix_mbox(self):
-        ### should be better!
-        import email.parser
-        fname = self.createMessage("cur", True)
-        n = 0
-        for msg in mailbox.PortableUnixMailbox(open(fname),
-                                               email.parser.Parser().parse):
-            n += 1
-            self.assertEqual(msg["subject"], "Simple Test")
-            # XXX Disabled until we figure out how to fix this
-            ##self.assertEqual(len(str(msg)), len(FROM_)+len(DUMMY_MESSAGE))
-        self.assertEqual(n, 1)
-
-## End: classes from the original module (for backward compatibility).
+## End: tests from the original module (for backward compatibility).
 
 
 _sample_message = """\