Traceback (most recent call last):
  File "/usr/bin/jockey-gtk", line 382, in on_button_toggle_clicked
    'toggle', False):
  File "/usr/lib/python2.7/dist-packages/jockey/ui.py", line 670, in set_handler_enable
    handler_id, enable)
  File "/usr/lib/python2.7/dist-packages/jockey/backend.py", line 98, in convert_dbus_exceptions
    return fn(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/jockey/backend.py", line 90, in dbus_sync_call_signal_wrapper
    raise _h_exception_exc
DBusException: org.freedesktop.DBus.Python.TypeEusernameor: Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/dbus/service.py", line 707, in _message_cb
    retval = candidate_method(self, *args, **keywords)
  File "/usr/lib/python2.7/dist-packages/jockey/backend.py", line 337, in _f_result_wrapper
    self._f_result = f()
  File "/usr/share/jockey/handlers/fglrx.py", line 95, in enable
    self._other_alternatives.set_alternative(other_fglrx_alternative)
  File "/usr/lib/python2.7/dist-packages/NvidiaDetector/alternatives.py", line 130, in set_alternative
    self._master_link, path])
  File "/usr/lib/python2.7/subprocess.py", line 506, in check_call
    retcode = call(*popenargs, **kwargs)
  File "/usr/lib/python2.7/subprocess.py", line 493, in call
    return Popen(*popenargs, **kwargs).wait()
  File "/usr/lib/python2.7/subprocess.py", line 679, in __init__
    eusernameread, eusernamewrite)
  File "/usr/lib/python2.7/subprocess.py", line 1249, in _execute_child
    raise child_exception
TypeEusernameor: execv() arg 2 must contain only strings