bzr: ERROR: sqlite3.OperationalError: unable to open database file

This was attempting a clean checkout from an SVN repository over ssh. It seemed to finish downloading all revisions, then failed with this error. I've anonymised the log.

Run command: bzr checkout svn+ssh://<email address hidden>/srv/svn/Documents C:\Users\Me\Development\DocumentsBzr
bzr: ERROR: sqlite3.OperationalError: unable to open database file

Traceback (most recent call last):
  File "bzrlib\commands.pyo", line 920, in exception_to_return_code
  File "bzrlib\commands.pyo", line 1131, in run_bzr
  File "bzrlib\commands.pyo", line 673, in run_argv_aliases
  File "bzrlib\commands.pyo", line 695, in run
  File "bzrlib\cleanup.pyo", line 136, in run_simple
  File "bzrlib\cleanup.pyo", line 166, in _do_with_cleanups
  File "C:/Program Files (x86)/Bazaar/plugins\qbzr\lib\commands.py", line 823, in run
  File "C:/Program Files (x86)/Bazaar/plugins\qbzr\lib\subprocess.py", line 920, in run_subprocess_command
  File "bzrlib\commands.pyo", line 1131, in run_bzr
  File "bzrlib\commands.pyo", line 673, in run_argv_aliases
  File "bzrlib\commands.pyo", line 695, in run
  File "bzrlib\cleanup.pyo", line 136, in run_simple
  File "bzrlib\cleanup.pyo", line 166, in _do_with_cleanups
  File "bzrlib\builtins.pyo", line 1628, in run
  File "bzrlib\controldir.pyo", line 779, in open_tree_or_branch
  File "bzrlib\controldir.pyo", line 459, in _get_tree_branch
  File "C:/Program Files (x86)/Bazaar/plugins\svn\remote.py", line 521, in open_branch
  File "C:/Program Files (x86)/Bazaar/plugins\svn\remote.py", line 446, in _determine_relpath
  File "C:/Program Files (x86)/Bazaar/plugins\svn\repository.py", line 738, in get_layout
  File "C:/Program Files (x86)/Bazaar/plugins\svn\repository.py", line 759, in get_layout_source
  File "C:/Program Files (x86)/Bazaar/plugins\svn\repository.py", line 785, in _find_guessed_layout
  File "C:/Program Files (x86)/Bazaar/plugins\svn\layout\guess.py", line 149, in repository_guess_layout
  File "C:/Program Files (x86)/Bazaar/plugins\svn\layout\guess.py", line 157, in logwalker_guess_layout
  File "C:/Program Files (x86)/Bazaar/plugins\svn\logwalker.py", line 278, in iter_changes
  File "C:/Program Files (x86)/Bazaar/plugins\svn\logwalker.py", line 363, in _fetch_revisions
  File "C:/Program Files (x86)/Bazaar/plugins\svn\transport.py", line 503, in get_log
  File "C:/Program Files (x86)/Bazaar/plugins\svn\logwalker.py", line 209, in __call__
  File "C:/Program Files (x86)/Bazaar/plugins\svn\cache\sqlitecache.py", line 381, in insert_paths
  File "C:/Program Files (x86)/Bazaar/plugins\svn\cache\sqlitecache.py", line 110, in executemany
OperationalError: unable to open database file

bzr 2.5.1 on python 2.6.6 (Windows-Vista-6.0.6002-SP2)
arguments: ['C:\\Program Files (x86)\\Bazaar\\bzr.exe', 'qsubprocess', '--
    bencode', 'l8:checkout50:svn+ssh://<email address hidden>/srv/svn/Document
    s37:C:\\Users\\Me\\Development\\DocumentsBzre']
plugins: bzrtools[2.5.0], changelog_merge[2.5.1], colo[0.4.0],
    explorer[1.2.2], fastimport[0.14.0dev], git[0.6.8], launchpad[2.5.1],
    loom[2.3.0dev], netrc_credential_store[2.5.1], news_merge[2.5.1],
    pipeline[1.4.0], qbzr[0.22.3], rewrite[0.6.4dev], svn[1.2.2],
    upload[1.2.0dev], xmloutput[0.8.8]
encoding: 'cp1252', fsenc: 'mbcs', lang: None

*** 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.