Crash opening a branch

[T.Parganas]

Run command: bzr branch http://bazaar.launchpad.net/~schooltool-owners/schooltool/st-book C:/st-book --bind --use-existing-dir
Doing on-the-fly conversion from RepositoryFormatKnitPack1() to RepositoryFormat2a().
This may take some time. Upgrade the repositories to the same format for better performance.
bzr: ERROR: exceptions.AttributeError: 'Inter1and2Helper' object has no attribute 'source_repo'

Traceback (most recent call last):
  File "bzrlib\commands.pyo", line 911, in exception_to_return_code
  File "bzrlib\commands.pyo", line 1111, in run_bzr
  File "bzrlib\commands.pyo", line 689, in run_argv_aliases
  File "bzrlib\commands.pyo", line 704, in run
  File "bzrlib\cleanup.pyo", line 135, in run_simple
  File "bzrlib\cleanup.pyo", line 165, in _do_with_cleanups
  File "C:/Program Files/Bazaar/plugins\qbzr\lib\commands.py", line 767, in run
  File "C:/Program Files/Bazaar/plugins\qbzr\lib\subprocess.py", line 869, in run_subprocess_command
  File "bzrlib\commands.pyo", line 1111, in run_bzr
  File "bzrlib\commands.pyo", line 689, in run_argv_aliases
  File "bzrlib\commands.pyo", line 704, in run
  File "bzrlib\cleanup.pyo", line 135, in run_simple
  File "bzrlib\cleanup.pyo", line 165, in _do_with_cleanups
  File "bzrlib\builtins.pyo", line 1246, in run
  File "bzrlib\bzrdir.pyo", line 1257, in sprout
  File "bzrlib\repository.pyo", line 1741, in fetch
  File "bzrlib\decorators.pyo", line 194, in write_locked
  File "bzrlib\repository.pyo", line 3449, in fetch
  File "bzrlib\fetch.pyo", line 73, in __init__
  File "bzrlib\fetch.pyo", line 99, in __fetch
  File "bzrlib\fetch.pyo", line 127, in _fetch_everything_for_search
  File "bzrlib\repository.pyo", line 4288, in insert_stream
  File "bzrlib\repository.pyo", line 4317, in _locked_insert_stream
  File "bzrlib\repository.pyo", line 4524, in get_stream
  File "bzrlib\repository.pyo", line 4493, in _generate_root_texts
  File "bzrlib\fetch.pyo", line 249, in generate_root_texts
AttributeError: 'Inter1and2Helper' object has no attribute 'source_repo'

bzr 2.2.0 on python 2.6.4 (Windows-XP-5.1.2600-SP3)
arguments: ['C:\\Program Files\\Bazaar\\bzr.exe', 'qsubprocess', '--bencode', 'l6:branch65:http://bazaar.launchpad.net/~schooltool-owners/schooltool/st-book10:C:/st-book6:--bind18:--use-existing-dire']
encoding: 'cp1253', fsenc: 'mbcs', lang: None
plugins:
  bzrtools C:\Program Files\Bazaar\plugins\bzrtools [2.2.0]
  colo C:\Program Files\Bazaar\plugins\colo [0.1.0]
  explorer C:\Program Files\Bazaar\plugins\explorer [1.1b1]
  fastimport C:\Program Files\Bazaar\plugins\fastimport [0.9.0dev]
  launchpad C:\Program Files\Bazaar\plugins\launchpad [2.2.0]
  loom C:\Program Files\Bazaar\plugins\loom [2.2.1dev]
  netrc_credential_store C:\Program Files\Bazaar\plugins\netrc_credential_store [2.2.0]
  news_merge C:\Program Files\Bazaar\plugins\news_merge [2.2.0]
  pipeline C:\Program Files\Bazaar\plugins\pipeline [unknown]
  qbzr C:\Program Files\Bazaar\plugins\qbzr [0.19.0]
  rewrite C:\Program Files\Bazaar\plugins\rewrite [0.6.0]
  svn C:\Program Files\Bazaar\plugins\svn [1.0.3]
  upload C:\Program Files\Bazaar\plugins\upload [1.0.0dev]
  xmloutput C:\Program Files\Bazaar\plugins\xmloutput [0.8.6]

*** Bazaar has encountered an internal error. This probably indicates a
    bug in Bazaar. You can help us fix it by filing a bug report at
        https://bugs.launchpad.net/bzr/+filebug
    including this traceback and a description of the problem.