traceback doing rspush (bzrlib.errors.ObjectNotLocked)

I was tring to rspush a branch on a remote server (first push, the remote branch didn't yet exits, but the empty directory was created)

I admit being clueless about rsync, so it may well be that I am doing something wrong, but still if that's the case it should give me a sensible error message instead of a traceback...

paolo@murdock:~/bzr/gedit$ bzr rspush --no-tree <email address hidden>:/home/users/pborelli/public_html/bzr/gedit
bzr: ERROR: bzrlib.errors.ObjectNotLocked: <WorkingTree4 of /home/paolo/bzr/gedit> is not locked

Traceback (most recent call last):
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 817, in run_bzr_catch_errors
    return run_bzr(argv)
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 779, in run_bzr
    ret = run(*run_argv)
  File "/usr/lib/python2.5/site-packages/bzrlib/plugins/bzrtools/command.py", line 13, in run_argv_aliases
    commands.Command.run_argv_aliases(self, argv, alias_argv)
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 477, in run_argv_aliases
    return self.run(**all_cmd_args)
  File "/usr/lib/python2.5/site-packages/bzrlib/plugins/bzrtools/__init__.py", line 636, in run
    working_tree=not no_tree)
  File "/usr/lib/python2.5/site-packages/bzrlib/plugins/bzrtools/bzrtools.py", line 260, in rspush
    for path, status, kind, file_id, entry in wt.list_files():
  File "/usr/lib/python2.5/site-packages/bzrlib/workingtree.py", line 1028, in list_files
    raise errors.ObjectNotLocked(self)
ObjectNotLocked: <WorkingTree4 of /home/paolo/bzr/gedit> is not locked

bzr 0.90.0 on python 2.5.1.final.0 (linux2)
arguments: ['/usr/bin/bzr', 'rspush', '--no-tree', '<email address hidden>:/home/users/pborelli/public_html/bzr/gedit']

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