Spurious test failure in pidfile.txt

PQM just failed with what looks to be a spurious failure in lib/canonical/lazr/doc/pidfile.txt:

Failure in test /srv/buildbot/slaves/launchpad/lucid-devel/build/lib/canonical/lazr/tests/../doc/pidfile.txt
Traceback (most recent call last):
  File "/usr/lib/python2.6/unittest.py", line 279, in run
    testMethod()
  File "/usr/lib/python2.6/doctest.py", line 2152, in runTest
    raise self.failureException(self.format_failure(new.getvalue()))
AssertionError: Failed doctest test for pidfile.txt
  File "/srv/buildbot/slaves/launchpad/lucid-devel/build/lib/canonical/lazr/tests/../doc/pidfile.txt", line 0

----------------------------------------------------------------------
File "/srv/buildbot/slaves/launchpad/lucid-devel/build/lib/canonical/lazr/tests/../doc/pidfile.txt", line 113, in pidfile.txt
Failed example:
    stop(pid, signal.SIGTERM)
Differences (ndiff with -expected +actual):
    - Stopped successfully
    + Error: pid file was not removed