tests fail if there's a /tmp/.bzr directory

These failures occur 100% of the time for me at the moment:

$ BZR_PLUGIN_PATH=-site:-user ./bzr selftest -s bb.test_outside_wt

bzr selftest: /home/andrew/warthogs/bzr/devel/bzr
   /home/andrew/warthogs/bzr/devel/bzrlib
   bzr-2.3.0dev4 python-2.6.6 Linux-2.6.35-22-generic-i686-with-Ubuntu-10.10-maverick

FAIL: blackbox.test_outside_wt.TestOutsideWT.test_cwd_log_cwd_log
    Text attachment: log
------------
0.281 creating repository in file:///tmp/testbzr-ujUNc4.tmp/.bzr/.
0.285 creating branch <bzrlib.branch.BzrBranchFormat7 object at 0x9f4e54c> in file:///tmp/testbzr-ujUNc4.tmp/
0.293 trying to create missing lock '/tmp/testbzr-ujUNc4.tmp/.bzr/checkout/dirstate'
0.294 opening working tree '/tmp/testbzr-ujUNc4.tmp'
0.299 run bzr: ['log']
0.299 bazaar version: 2.3.0dev4
0.299 bzr arguments: ['log']
0.301 encoding stdout as sys.stdout encoding 'UTF-8'
0.307 Traceback (most recent call last):
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 1231, in run_bzr_catch_user_errors
    return run_bzr(argv)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 1123, in run_bzr
    ret = run(*run_argv)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 691, in run_argv_aliases
    return self.run(**all_cmd_args)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 710, in run
    return self._operation.run_simple(*args, **kwargs)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/cleanup.py", line 135, in run_simple
    self.cleanups, self.func, *args, **kwargs)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/cleanup.py", line 165, in _do_with_cleanups
    result = func(*args, **kwargs)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 1138, in ignore_pipe
    result = func(*args, **kwargs)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/builtins.py", line 2393, in run
    b = dir.open_branch()
  File "/home/andrew/warthogs/bzr/devel/bzrlib/bzrdir.py", line 1424, in open_branch
    format = self.find_branch_format(name=name)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/bzrdir.py", line 1312, in find_branch_format
    return BranchFormat.find_format(self, name=name)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/branch.py", line 1570, in find_format
    raise errors.NotBranchError(path=transport.base, bzrdir=a_bzrdir)
NotBranchError: Not a branch: "/tmp/.bzr/branch/": location is a repository.

0.307 errors:
'bzr: ERROR: Not a branch: "/tmp/.bzr/branch/": location is a repository.\n'
0.311 opening working tree '/tmp/testbzr-ujUNc4.tmp'
------------
Text attachment: traceback
------------
Traceback (most recent call last):
  File "/usr/lib/python2.6/dist-packages/testtools/runtest.py", line 144, in _run_user
    return fn(*args)
  File "/usr/lib/python2.6/dist-packages/testtools/testcase.py", line 465, in _run_test_method
    testMethod()
  File "/home/andrew/warthogs/bzr/devel/bzrlib/tests/blackbox/test_outside_wt.py", line 43, in test_cwd_log
    err)
AssertionError: not equal:
a = u'bzr: ERROR: Not a branch: "/tmp/tmpDw73s1/".\n'
b = 'bzr: ERROR: Not a branch: "/tmp/.bzr/branch/": location is a repository.\n'

------------

FAIL: blackbox.test_outside_wt.TestOutsideWT.test_diff_outside_tree_diff_outside_tree
    Text attachment: log
------------
0.315 creating repository in file:///tmp/testbzr-ujUNc4.tmp/bzrlib.tests.blackbox.test_outside_wt.TestOutsideWT.test_diff_outside_tree/work/branch1/.bzr/.
0.317 creating branch <bzrlib.branch.BzrBranchFormat7 object at 0xa57806c> in file:///tmp/testbzr-ujUNc4.tmp/bzrlib.tests.blackbox.test_outside_wt.TestOutsideWT.test_diff_outside_tree/work/branch1/
0.324 trying to create missing lock '/tmp/testbzr-ujUNc4.tmp/bzrlib.tests.blackbox.test_outside_wt.TestOutsideWT.test_diff_outside_tree/work/branch1/.bzr/checkout/dirstate'
0.325 opening working tree '/tmp/testbzr-ujUNc4.tmp/bzrlib.tests.blackbox.test_outside_wt.TestOutsideWT.test_diff_outside_tree/work/branch1'
0.332 preparing to commit
    INFO Committing to: /tmp/testbzr-ujUNc4.tmp/bzrlib.tests.blackbox.test_outside_wt.TestOutsideWT.test_diff_outside_tree/work/branch1/
0.335 Selecting files for commit with filter None
    INFO Committed revision 1.
0.347 Committed revid <email address hidden> as revno 1.
0.351 preparing to commit
    INFO Committing to: /tmp/testbzr-ujUNc4.tmp/bzrlib.tests.blackbox.test_outside_wt.TestOutsideWT.test_diff_outside_tree/work/branch1/
0.353 Selecting files for commit with filter None
    INFO Committed revision 2.
0.360 Committed revid <email address hidden> as revno 2.
0.361 run bzr: ['diff', '-r', 'revno:2:branch2..revno:1']
0.361 bazaar version: 2.3.0dev4
0.361 bzr arguments: ['diff', '-r', 'revno:2:branch2..revno:1']
0.371 Returning RevisionSpec RevisionSpec_revno for revno:2:branch2
0.371 Returning RevisionSpec RevisionSpec_revno for revno:1
0.372 encoding stdout as sys.stdout encoding 'UTF-8'
0.375 Traceback (most recent call last):
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 1231, in run_bzr_catch_user_errors
    return run_bzr(argv)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 1123, in run_bzr
    ret = run(*run_argv)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 691, in run_argv_aliases
    return self.run(**all_cmd_args)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 710, in run
    return self._operation.run_simple(*args, **kwargs)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/cleanup.py", line 135, in run_simple
    self.cleanups, self.func, *args, **kwargs)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/cleanup.py", line 165, in _do_with_cleanups
    result = func(*args, **kwargs)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 1138, in ignore_pipe
    result = func(*args, **kwargs)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/builtins.py", line 2004, in run
    file_list, revision, old, new, self.add_cleanup, apply_view=True)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/diff.py", line 397, in get_trees_and_branches_to_diff_locked
    bzrdir.BzrDir.open_containing_tree_or_branch(old_url)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/bzrdir.py", line 820, in open_containing_tree_or_branch
    tree, branch = bzrdir._get_tree_branch()
  File "/home/andrew/warthogs/bzr/devel/bzrlib/controldir.py", line 537, in _get_tree_branch
    branch = self.open_branch(name=name)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/bzrdir.py", line 1424, in open_branch
    format = self.find_branch_format(name=name)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/bzrdir.py", line 1312, in find_branch_format
    return BranchFormat.find_format(self, name=name)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/branch.py", line 1570, in find_format
    raise errors.NotBranchError(path=transport.base, bzrdir=a_bzrdir)
NotBranchError: Not a branch: "/tmp/.bzr/branch/": location is a repository.

0.375 errors:
'bzr: ERROR: Not a branch: "/tmp/.bzr/branch/": location is a repository.\n'
0.378 opening working tree '/tmp/testbzr-ujUNc4.tmp'
------------
Text attachment: traceback
------------
Traceback (most recent call last):
  File "/usr/lib/python2.6/dist-packages/testtools/runtest.py", line 144, in _run_user
    return fn(*args)
  File "/usr/lib/python2.6/dist-packages/testtools/testcase.py", line 465, in _run_test_method
    testMethod()
  File "/home/andrew/warthogs/bzr/devel/bzrlib/tests/blackbox/test_outside_wt.py", line 68, in test_diff_outside_tree
    self.assertEqual(expected_error, err)
AssertionError: not equal:
a = u'bzr: ERROR: Not a branch: "/tmp/tmpNsYyOG/branch2/".\n'
b = 'bzr: ERROR: Not a branch: "/tmp/.bzr/branch/": location is a repository.\n'

------------

======================================================================
FAIL: bzrlib.tests.blackbox.test_outside_wt.TestOutsideWT.test_cwd_log
----------------------------------------------------------------------
_StringException: Text attachment: log
------------
0.281 creating repository in file:///tmp/testbzr-ujUNc4.tmp/.bzr/.
0.285 creating branch <bzrlib.branch.BzrBranchFormat7 object at 0x9f4e54c> in file:///tmp/testbzr-ujUNc4.tmp/
0.293 trying to create missing lock '/tmp/testbzr-ujUNc4.tmp/.bzr/checkout/dirstate'
0.294 opening working tree '/tmp/testbzr-ujUNc4.tmp'
0.299 run bzr: ['log']
0.299 bazaar version: 2.3.0dev4
0.299 bzr arguments: ['log']
0.301 encoding stdout as sys.stdout encoding 'UTF-8'
0.307 Traceback (most recent call last):
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 1231, in run_bzr_catch_user_errors
    return run_bzr(argv)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 1123, in run_bzr
    ret = run(*run_argv)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 691, in run_argv_aliases
    return self.run(**all_cmd_args)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 710, in run
    return self._operation.run_simple(*args, **kwargs)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/cleanup.py", line 135, in run_simple
    self.cleanups, self.func, *args, **kwargs)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/cleanup.py", line 165, in _do_with_cleanups
    result = func(*args, **kwargs)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 1138, in ignore_pipe
    result = func(*args, **kwargs)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/builtins.py", line 2393, in run
    b = dir.open_branch()
  File "/home/andrew/warthogs/bzr/devel/bzrlib/bzrdir.py", line 1424, in open_branch
    format = self.find_branch_format(name=name)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/bzrdir.py", line 1312, in find_branch_format
    return BranchFormat.find_format(self, name=name)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/branch.py", line 1570, in find_format
    raise errors.NotBranchError(path=transport.base, bzrdir=a_bzrdir)
NotBranchError: Not a branch: "/tmp/.bzr/branch/": location is a repository.

0.307 errors:
'bzr: ERROR: Not a branch: "/tmp/.bzr/branch/": location is a repository.\n'
0.311 opening working tree '/tmp/testbzr-ujUNc4.tmp'
------------
Text attachment: traceback
------------
Traceback (most recent call last):
  File "/usr/lib/python2.6/dist-packages/testtools/runtest.py", line 144, in _run_user
    return fn(*args)
  File "/usr/lib/python2.6/dist-packages/testtools/testcase.py", line 465, in _run_test_method
    testMethod()
  File "/home/andrew/warthogs/bzr/devel/bzrlib/tests/blackbox/test_outside_wt.py", line 43, in test_cwd_log
    err)
AssertionError: not equal:
a = u'bzr: ERROR: Not a branch: "/tmp/tmpDw73s1/".\n'
b = 'bzr: ERROR: Not a branch: "/tmp/.bzr/branch/": location is a repository.\n'

------------

======================================================================
FAIL: bzrlib.tests.blackbox.test_outside_wt.TestOutsideWT.test_diff_outside_tree
----------------------------------------------------------------------
_StringException: Text attachment: log
------------
0.315 creating repository in file:///tmp/testbzr-ujUNc4.tmp/bzrlib.tests.blackbox.test_outside_wt.TestOutsideWT.test_diff_outside_tree/work/branch1/.bzr/.
0.317 creating branch <bzrlib.branch.BzrBranchFormat7 object at 0xa57806c> in file:///tmp/testbzr-ujUNc4.tmp/bzrlib.tests.blackbox.test_outside_wt.TestOutsideWT.test_diff_outside_tree/work/branch1/
0.324 trying to create missing lock '/tmp/testbzr-ujUNc4.tmp/bzrlib.tests.blackbox.test_outside_wt.TestOutsideWT.test_diff_outside_tree/work/branch1/.bzr/checkout/dirstate'
0.325 opening working tree '/tmp/testbzr-ujUNc4.tmp/bzrlib.tests.blackbox.test_outside_wt.TestOutsideWT.test_diff_outside_tree/work/branch1'
0.332 preparing to commit
    INFO Committing to: /tmp/testbzr-ujUNc4.tmp/bzrlib.tests.blackbox.test_outside_wt.TestOutsideWT.test_diff_outside_tree/work/branch1/
0.335 Selecting files for commit with filter None
    INFO Committed revision 1.
0.347 Committed revid <email address hidden> as revno 1.
0.351 preparing to commit
    INFO Committing to: /tmp/testbzr-ujUNc4.tmp/bzrlib.tests.blackbox.test_outside_wt.TestOutsideWT.test_diff_outside_tree/work/branch1/
0.353 Selecting files for commit with filter None
    INFO Committed revision 2.
0.360 Committed revid <email address hidden> as revno 2.
0.361 run bzr: ['diff', '-r', 'revno:2:branch2..revno:1']
0.361 bazaar version: 2.3.0dev4
0.361 bzr arguments: ['diff', '-r', 'revno:2:branch2..revno:1']
0.371 Returning RevisionSpec RevisionSpec_revno for revno:2:branch2
0.371 Returning RevisionSpec RevisionSpec_revno for revno:1
0.372 encoding stdout as sys.stdout encoding 'UTF-8'
0.375 Traceback (most recent call last):
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 1231, in run_bzr_catch_user_errors
    return run_bzr(argv)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 1123, in run_bzr
    ret = run(*run_argv)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 691, in run_argv_aliases
    return self.run(**all_cmd_args)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 710, in run
    return self._operation.run_simple(*args, **kwargs)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/cleanup.py", line 135, in run_simple
    self.cleanups, self.func, *args, **kwargs)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/cleanup.py", line 165, in _do_with_cleanups
    result = func(*args, **kwargs)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/commands.py", line 1138, in ignore_pipe
    result = func(*args, **kwargs)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/builtins.py", line 2004, in run
    file_list, revision, old, new, self.add_cleanup, apply_view=True)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/diff.py", line 397, in get_trees_and_branches_to_diff_locked
    bzrdir.BzrDir.open_containing_tree_or_branch(old_url)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/bzrdir.py", line 820, in open_containing_tree_or_branch
    tree, branch = bzrdir._get_tree_branch()
  File "/home/andrew/warthogs/bzr/devel/bzrlib/controldir.py", line 537, in _get_tree_branch
    branch = self.open_branch(name=name)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/bzrdir.py", line 1424, in open_branch
    format = self.find_branch_format(name=name)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/bzrdir.py", line 1312, in find_branch_format
    return BranchFormat.find_format(self, name=name)
  File "/home/andrew/warthogs/bzr/devel/bzrlib/branch.py", line 1570, in find_format
    raise errors.NotBranchError(path=transport.base, bzrdir=a_bzrdir)
NotBranchError: Not a branch: "/tmp/.bzr/branch/": location is a repository.

0.375 errors:
'bzr: ERROR: Not a branch: "/tmp/.bzr/branch/": location is a repository.\n'
0.378 opening working tree '/tmp/testbzr-ujUNc4.tmp'
------------
Text attachment: traceback
------------
Traceback (most recent call last):
  File "/usr/lib/python2.6/dist-packages/testtools/runtest.py", line 144, in _run_user
    return fn(*args)
  File "/usr/lib/python2.6/dist-packages/testtools/testcase.py", line 465, in _run_test_method
    testMethod()
  File "/home/andrew/warthogs/bzr/devel/bzrlib/tests/blackbox/test_outside_wt.py", line 68, in test_diff_outside_tree
    self.assertEqual(expected_error, err)
AssertionError: not equal:
a = u'bzr: ERROR: Not a branch: "/tmp/tmpNsYyOG/branch2/".\n'
b = 'bzr: ERROR: Not a branch: "/tmp/.bzr/branch/": location is a repository.\n'

------------

----------------------------------------------------------------------
Ran 3 tests in 0.208s

FAILED (failures=2)

$ bzr revision-info
5538 <email address hidden>