bzr update crashes with 'AssertionError: name already in parent'

May be a duplicate of bug # 377261, but not certain. Traceback follows.

jlefkowitz@<hostname>$ bzr up
bzr: ERROR: exceptions.AssertionError: name u'media' already in parent

Traceback (most recent call last):
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 842, in exception_to_return_code
    return the_callable(*args, **kwargs)
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 1037, in run_bzr
    ret = run(*run_argv)
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 654, in run_argv_aliases
    return self.run(**all_cmd_args)
  File "/usr/lib/python2.5/site-packages/bzrlib/builtins.py", line 1413, in run
    view_info=view_info), possible_transports=possible_transports)
  File "/usr/lib/python2.5/site-packages/bzrlib/workingtree.py", line 2216, in update
    return self._update_tree(old_tip, change_reporter)
  File "/usr/lib/python2.5/site-packages/bzrlib/mutabletree.py", line 53, in tree_write_locked
    return unbound(self, *args, **kwargs)
  File "/usr/lib/python2.5/site-packages/bzrlib/workingtree.py", line 2256, in _update_tree
    change_reporter=change_reporter)
  File "/usr/lib/python2.5/site-packages/bzrlib/merge.py", line 1567, in merge_inner
    return merger.do_merge()
  File "/usr/lib/python2.5/site-packages/bzrlib/merge.py", line 508, in do_merge
    self._do_merge_to(merge)
  File "/usr/lib/python2.5/site-packages/bzrlib/merge.py", line 480, in _do_merge_to
    merge.do_merge()
  File "/usr/lib/python2.5/site-packages/bzrlib/merge.py", line 620, in do_merge
    self._compute_transform()
  File "/usr/lib/python2.5/site-packages/bzrlib/merge.py", line 652, in _compute_transform
    entries = self._entries3()
  File "/usr/lib/python2.5/site-packages/bzrlib/merge.py", line 702, in _entries3
    self.interesting_ids))
  File "/usr/lib/python2.5/site-packages/bzrlib/decorators.py", line 138, in read_locked
    result = unbound(self, *args, **kwargs)
  File "/usr/lib/python2.5/site-packages/bzrlib/tree.py", line 201, in iter_entries_by_dir
    return self.inventory.iter_entries_by_dir(
  File "/usr/lib/python2.5/site-packages/bzrlib/workingtree_4.py", line 401, in _get_inventory
    self._generate_inventory()
  File "/usr/lib/python2.5/site-packages/bzrlib/workingtree_4.py", line 337, in _generate_inventory
    % (name_unicode,))
AssertionError: name u'media' already in parent

bzr 2.0.3 on python 2.5.2 (Linux-2.6.35.4-rscloud-x86_64-with-debian-5.0.8)
arguments: ['/usr/bin/bzr', 'up']
encoding: 'UTF-8', fsenc: 'UTF-8', lang: 'en_US.UTF-8'
plugins:
  launchpad /usr/lib/python2.5/site-packages/bzrlib/plugins/launchpad [2.0.3]
  netrc_credential_store /usr/lib/python2.5/site-packages/bzrlib/plugins/netrc_credential_store [2.0.3]

*** 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.