encoding problem with `bzr merge --preview | less`

[Alexander Belchenko]

C:\work\Bazaar\mydev.packs\disable.bzr.log>bzr --no-plugins merge --preview|less
bzr: ERROR: exceptions.AssertionError: you cannot specify None for the display encoding.

Traceback (most recent call last):
  File "bzrlib\commands.pyc", line 834, in run_bzr_catch_errors
  File "bzrlib\commands.pyc", line 790, in run_bzr
  File "bzrlib\commands.pyc", line 492, in run_argv_aliases
  File "bzrlib\builtins.pyc", line 2846, in run
  File "bzrlib\builtins.pyc", line 2917, in _get_merger_from_branch
  File "bzrlib\builtins.pyc", line 2984, in _select_branch_location
  File "bzrlib\builtins.pyc", line 3001, in _get_remembered
  File "bzrlib\urlutils.pyc", line 576, in unescape_for_display
AssertionError: you cannot specify None for the display encoding.

bzr 1.2.0 on python 2.5.1.final.0 (win32)
arguments: ['C:\\Program Files\\Bazaar\\bzr.EXE', '--no-plugins', 'merge', '--preview']
encoding: 'cp1251', fsenc: 'mbcs', lang: 'ru'
plugins:
*** Bazaar has encountered an internal error.
    Please report a bug at https://bugs.launchpad.net/bzr/+filebug
    including this traceback, and a description of what you
    were doing when the error occurred.