[i18n] `bzr help` does not work

[IWATA Hidetaka]

When i18n is activated, `bzr help` raises UnicodeError

`bzr help command-name` does not work, but `bzr command-name --help` works correctly.
Both had worked with bzr-2.5b6.

>bzr help diff
bzr: ERROR: exceptions.UnicodeEncodeError: 'ascii' codec can't encode characters in position 9-36: ordinal not in r

Traceback (most recent call last):
  File "C:\DEVELOP\py_envs\bzr2.5-py26\lib\site-packages\bzrlib\commands.py", line 920, in exception_to_return_code
    return the_callable(*args, **kwargs)
  File "C:\DEVELOP\py_envs\bzr2.5-py26\lib\site-packages\bzrlib\commands.py", line 1131, in run_bzr
    ret = run(*run_argv)
  File "C:\DEVELOP\py_envs\bzr2.5-py26\lib\site-packages\bzrlib\commands.py", line 673, in run_argv_aliases
    return self.run(**all_cmd_args)
  File "C:\DEVELOP\py_envs\bzr2.5-py26\lib\site-packages\bzrlib\commands.py", line 695, in run
    return self._operation.run_simple(*args, **kwargs)
  File "C:\DEVELOP\py_envs\bzr2.5-py26\lib\site-packages\bzrlib\cleanup.py", line 136, in run_simple
    self.cleanups, self.func, *args, **kwargs)
  File "C:\DEVELOP\py_envs\bzr2.5-py26\lib\site-packages\bzrlib\cleanup.py", line 166, in _do_with_cleanups
    result = func(*args, **kwargs)
  File "C:\DEVELOP\py_envs\bzr2.5-py26\lib\site-packages\bzrlib\commands.py", line 1148, in ignore_pipe
    result = func(*args, **kwargs)
  File "C:\DEVELOP\py_envs\bzr2.5-py26\lib\site-packages\bzrlib\builtins.py", line 4815, in run
    bzrlib.help.help(topic)
  File "C:\DEVELOP\py_envs\bzr2.5-py26\lib\site-packages\bzrlib\help.py", line 53, in help
    outfile.write(source.get_help_text(shadowed_terms))
UnicodeEncodeError: 'ascii' codec can't encode characters in position 9-36: ordinal not in range(128)

bzr 2.5.0 on python 2.6.6 (Windows-7-6.1.7601-SP1)
arguments: ['C:\\DEVELOP\\py_envs\\bzr2.5-py26\\Scripts\\bzr', 'help', 'diff']
plugins: bash_completion[2.5.0], changelog_merge[2.5.0], launchpad[2.5.0],
    netrc_credential_store[2.5.0], news_merge[2.5.0], po_merge[2.5.0],
    weave_fmt[2.5.0]
encoding: 'cp932', fsenc: 'mbcs', lang: 'ja'

[Martin Packman (gz)]

Combining with an exiting bug report about this against bzr on ubuntu.