Clicking refresh button in qlog causes crash

[Nicholas Allen]

If I click the refresh button in qlog I get the following crash report:

bzr: ERROR: exceptions.AttributeError: 'QLogGraphProvider' object has no attribute 'unlock_repos'

Traceback (most recent call last):
  File "/home/nick/.bazaar/plugins/qbzr/lib/trace.py", line 222, in reports_exception_decorate
    return f(*args, **kargs)
  File "/home/nick/.bazaar/plugins/qbzr/lib/log.py", line 257, in refresh
    self.log_list.refresh()
  File "/home/nick/.bazaar/plugins/qbzr/lib/logwidget.py", line 158, in refresh
    self.graph_provider.unlock_repos()
AttributeError: 'QLogGraphProvider' object has no attribute 'unlock_repos'

bzr 1.15dev on python 2.6.2 (linux2)
arguments: ['/usr/local/bin/bzr', 'qlog']
encoding: 'UTF-8', fsenc: 'UTF-8', lang: 'en_GB.UTF-8'
plugins:
  bzrtools /home/nick/.bazaar/plugins/bzrtools [1.14]
  difftools /home/nick/.bazaar/plugins/difftools [0.91]
  launchpad /usr/local/lib/python2.6/dist-packages/bzrlib/plugins/launchpad [unknown]
  mirror /home/nick/.bazaar/plugins/mirror [unknown]
  netrc_credential_store /usr/local/lib/python2.6/dist-packages/bzrlib/plugins/netrc_credential_store [unknown]
  qbzr /home/nick/.bazaar/plugins/qbzr [0.10dev]
  rebase /home/nick/.bazaar/plugins/rebase [0.4.1]
  search /home/nick/.bazaar/plugins/search [1.7dev]
  webdav /home/nick/.bazaar/plugins/webdav [1.12]
  xmloutput /home/nick/.bazaar/plugins/xmloutput [0.5]