'AttributeError: 'NoneType' object has no attribute 'exclude'' when run in conjunction with coverage plugin

[kacarstensen-shift]

Full traceback (one from each test runner worker):

Traceback (most recent call last):
  File "/Users/kacarstensen/Documents/work/shift-virtualenv/lib/python2.7/site-packages/nose_gevented_multiprocess/nose_gevented_multiprocess.py", line 1034, in <module>
    individual_client_starter()
  File "/Users/kacarstensen/Documents/work/shift-virtualenv/lib/python2.7/site-packages/nose_gevented_multiprocess/nose_gevented_multiprocess.py", line 1031, in individual_client_starter
    start_test_processor_task_runner(worker_id, server_port)
  File "/Users/kacarstensen/Documents/work/shift-virtualenv/lib/python2.7/site-packages/nose_gevented_multiprocess/nose_gevented_multiprocess.py", line 482, in start_test_processor_task_runner
    task_runner.run_until_done()
  File "/Users/kacarstensen/Documents/work/shift-virtualenv/lib/python2.7/site-packages/nose_gevented_multiprocess/nose_gevented_multiprocess.py", line 216, in run_until_done
    self.setup()
  File "/Users/kacarstensen/Documents/work/shift-virtualenv/lib/python2.7/site-packages/nose_gevented_multiprocess/nose_gevented_multiprocess.py", line 369, in setup
    pickle.loads(str(config_serialized))
  File "/Users/kacarstensen/Documents/work/shift-virtualenv/lib/python2.7/site-packages/nose_gevented_multiprocess/nose_gevented_multiprocess.py", line 358, in _set_up_base_test_components
    self.prepare_config_plugins(config)
  File "/Users/kacarstensen/Documents/work/shift-virtualenv/lib/python2.7/site-packages/nose_gevented_multiprocess/nose_gevented_multiprocess.py", line 382, in prepare_config_plugins
    config.plugins.begin()
  File "/Users/kacarstensen/Documents/work/shift-virtualenv/lib/python2.7/site-packages/nose/plugins/manager.py", line 99, in __call__
    return self.call(*arg, **kw)
  File "/Users/kacarstensen/Documents/work/shift-virtualenv/lib/python2.7/site-packages/nose/plugins/manager.py", line 167, in simple
    result = meth(*arg, **kw)
  File "/Users/kacarstensen/Documents/work/shift-virtualenv/lib/python2.7/site-packages/nose/plugins/cover.py", line 155, in begin
    self.coverInstance.exclude('#pragma[: ]+[nN][oO] [cC][oO][vV][eE][rR]')
AttributeError: 'NoneType' object has no attribute 'exclude'

Coverage options (from my .noserc):

with-coverage=1
cover-html=1
cover-package=ge
cover-branches=1
cover-erase=1

Using Python 2.7.2, coverage 3.7.1.