Index: Doc/library/argparse.rst
===================================================================
--- Doc/library/argparse.rst	(revision 83505)
+++ Doc/library/argparse.rst	(working copy)
@@ -203,8 +203,8 @@
 add_help
 ^^^^^^^^
 
-By default, ArgumentParser objects add a ``-h/--help`` option which simply
-displays the parser's help message.  For example, consider a file named
+By default, ArgumentParser objects add an option which simply displays
+the parser's help message. For example, consider a file named
 ``myprogram.py`` containing the following code::
 
    import argparse
@@ -234,12 +234,27 @@
    optional arguments:
     --foo FOO  foo help
 
+The help option is typically ``-h/--help``. The exception to this is
+if the ``prefix_chars=`` is specified and does not include ``'-'``, in
+which case ``-h`` and ``--help`` are not valid options.  In
+this case, the first character in ``prefix_chars`` is used to prefix
+the help options::  
 
+   >>> parser = argparse.ArgumentParser(prog='PROG', prefix_chars='+/')
+   >>> parser.print_help()
+   usage: PROG [+h]
+
+   optional arguments:
+     +h, ++help  show this help message and exit
+
+
+
 prefix_chars
 ^^^^^^^^^^^^
 
 Most command-line options will use ``'-'`` as the prefix, e.g. ``-f/--foo``.
-Parsers that need to support additional prefix characters, e.g. for options
+Parsers that need to support different or additional prefix
+characters, e.g. for options
 like ``+f`` or ``/foo``, may specify them using the ``prefix_chars=`` argument
 to the ArgumentParser constructor::
 
Index: Lib/argparse.py
===================================================================
--- Lib/argparse.py	(revision 83505)
+++ Lib/argparse.py	(working copy)
@@ -1561,13 +1561,16 @@
 
         # add help and version arguments if necessary
         # (using explicit default to override global argument_default)
+        default_prefix = '-' if '-' in prefix_chars else prefix_chars[0]
         if self.add_help:
             self.add_argument(
-                '-h', '--help', action='help', default=SUPPRESS,
+                default_prefix+'h', default_prefix*2+'help',
+                action='help', default=SUPPRESS,
                 help=_('show this help message and exit'))
         if self.version:
             self.add_argument(
-                '-v', '--version', action='version', default=SUPPRESS,
+                default_prefix+'v', default_prefix*2+'version',
+                action='version', default=SUPPRESS,
                 version=self.version,
                 help=_("show program's version number and exit"))