$ bzr init main
Created a standalone tree (format: 2a)                                                                                                                                      
$ bzr init sub1
Created a standalone tree (format: 2a)                                                                                                                                      
$ cd main/
$ bzr eadd ../sub1 sub1
Add external branch ../sub1 sub1
Branched 0 revision(s).                                                                                                                                                     
adding .bzrignore
adding .bzrmeta
adding .bzrmeta/externals
adding .bzrmeta/externals-snapshot

$ bzr ci -m "Add sub1"
Committing to: /home/etarasenko/projects/bzr-externals/main/                                                                                                                
added .bzrignore
added .bzrmeta
added .bzrmeta/externals
added .bzrmeta/externals-snapshot
bzr: ERROR: bzrlib.errors.IllegalUseOfScopeReplacer: ScopeReplacer object 'cmdline' was used incorrectly: Object already cleaned up, did you assign it to another variable?: _factory

Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 946, in exception_to_return_code
    return the_callable(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 1150, in run_bzr
    ret = run(*run_argv)
  File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 699, in run_argv_aliases
    return self.run(**all_cmd_args)
  File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 721, in run
    return self._operation.run_simple(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/cleanup.py", line 135, in run_simple
    self.cleanups, self.func, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/cleanup.py", line 165, in _do_with_cleanups
    result = func(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/builtins.py", line 3316, in run
    lossy=lossy)
  File "/usr/lib/python2.7/dist-packages/bzrlib/decorators.py", line 217, in write_locked
    result = unbound(self, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/workingtree_4.py", line 209, in commit
    result = WorkingTree.commit(self, message, revprops, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/decorators.py", line 217, in write_locked
    result = unbound(self, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/mutabletree.py", line 210, in commit
    *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/commit.py", line 289, in commit
    lossy=lossy)
  File "/usr/lib/python2.7/dist-packages/bzrlib/cleanup.py", line 131, in run
    self.cleanups, self.func, self, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/cleanup.py", line 165, in _do_with_cleanups
    result = func(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/commit.py", line 462, in _commit
    self.branch.set_last_revision_info(new_revno, self.rev_id)
  File "/usr/lib/python2.7/dist-packages/bzrlib/decorators.py", line 217, in write_locked
    result = unbound(self, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/branch.py", line 2521, in set_last_revision_info
    self._run_post_change_branch_tip_hooks(old_revno, old_revid)
  File "/usr/lib/python2.7/dist-packages/bzrlib/branch.py", line 1221, in _run_post_change_branch_tip_hooks
    hook(params)
  File "/home/etarasenko/.bazaar/plugins/externals/__init__.py", line 75, in post_change_branch_tip_hook
    lazy_externals.Externals(params.branch, params.new_revid).pull()
  File "/home/etarasenko/.bazaar/plugins/externals/externals.py", line 157, in pull
    self.read_config()
  File "/home/etarasenko/.bazaar/plugins/externals/externals.py", line 61, in read_config
    self._set_config(f.read())
  File "/home/etarasenko/.bazaar/plugins/externals/externals.py", line 50, in _set_config
    arg = cmdline.split(line)
  File "/usr/lib/python2.7/dist-packages/bzrlib/lazy_import.py", line 110, in __getattribute__
    obj = _replace()
  File "/usr/lib/python2.7/dist-packages/bzrlib/lazy_import.py", line 89, in _replace
    extra=e)
IllegalUseOfScopeReplacer: ScopeReplacer object 'cmdline' was used incorrectly: Object already cleaned up, did you assign it to another variable?: _factory

bzr 2.4.1 on python 2.7.2 (Linux-3.0.0-12-generic-i686-with-LinuxMint-12-lisa)
arguments: ['/usr/bin/bzr', 'ci', '-m', 'Add sub1']
plugins: bash_completion[2.4.1], bzrtools[2.4.0], changelog_merge[2.4.1],
    externals[1.3.2], launchpad[2.4.1], netrc_credential_store[2.4.1],
    news_merge[2.4.1], qbzr[0.21.1], weave_fmt[2.4.1]
encoding: 'UTF-8', fsenc: 'UTF-8', lang: 'ru_RU.UTF-8'

*** 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.