bzr unshelve tracebacks when given a non-integer

% bzr unshelve all
bzr: ERROR: exceptions.ValueError: invalid literal for int() with base 10: 'all'

Traceback (most recent call last):
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 893, in run_bzr_catch_errors
    return run_bzr(argv)
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 839, in run_bzr
    ret = run(*run_argv)
  File "/usr/lib/python2.5/site-packages/bzrlib/commands.py", line 539, in run_argv_aliases
    return self.run(**all_cmd_args)
  File "/usr/lib/python2.5/site-packages/bzrlib/builtins.py", line 4910, in run
    Unshelver.from_args(shelf_id, action).run()
  File "/usr/lib/python2.5/site-packages/bzrlib/shelf_ui.py", line 226, in from_args
    shelf_id = int(shelf_id)
ValueError: invalid literal for int() with base 10: 'all'

bzr 1.11 on python 2.5.2 (linux2)
arguments: ['/usr/bin/bzr', 'unshelve', 'all']
encoding: 'UTF-8', fsenc: 'UTF-8', lang: 'en_US.UTF-8'
plugins:
  bisect /home/barry/.bazaar/plugins/bisect [1.1.0.pre.0]
  gtk /usr/lib/python2.5/site-packages/bzrlib/plugins/gtk [0.95.0.final.1]
  launchpad /usr/lib/python2.5/site-packages/bzrlib/plugins/launchpad [unknown]
  loom /home/barry/.bazaar/plugins/loom [1.4dev]
  lpreview /home/barry/.bazaar/plugins/lpreview [unknown]
  netrc_credential_store /usr/lib/python2.5/site-packages/bzrlib/plugins/netrc_credential_store [unknown]
  pqm /home/barry/.bazaar/plugins/pqm [1.4dev]
  touch /home/barry/.bazaar/plugins/touch [unknown]
*** Bazaar has encountered an internal error.
    Please report a bug at https://bugs.launchpad.net/bzr/+filebug
    including this traceback, and a description of what you
    were doing when the error occurred.