Traceback (most recent call last):
  File "/data/buildbot/lib/python/buildbot/process/buildstep.py", line 649, in startStep
    d.addCallback(self._startStep_2)
  File "/usr/lib/python2.4/site-packages/twisted/internet/defer.py", line 191, in addCallback
    callbackKeywords=kw)
  File "/usr/lib/python2.4/site-packages/twisted/internet/defer.py", line 182, in addCallbacks
    self._runCallbacks()
  File "/usr/lib/python2.4/site-packages/twisted/internet/defer.py", line 307, in _runCallbacks
    self.result = callback(self.result, *args, **kw)
--- <exception caught here> ---
  File "/data/buildbot/lib/python/buildbot/process/buildstep.py", line 672, in _startStep_2
    skip = self.start()
  File "/data/buildbot/lib/python/buildbot/steps/source.py", line 173, in start
    self.startVC(branch, revision, patch)
  File "/data/buildbot/lib/python/buildbot/steps/source.py", line 418, in startVC
    raise BuildSlaveTooOldError(m)
buildbot.interfaces.BuildSlaveTooOldError: This buildslave (heller-windows-amd64) does not know about multiple branches, and using mode=update would probably build the wrong tree. Refusing to build. Please upgrade the buildslave to buildbot-0.7.0 or newer.