2012-03-07 13:31:07,874 - softwarecenter.backend.reviews - WARNING - Could not get usefulness from server, no username in config file
2012-03-07 13:31:40,819 - softwarecenter.ui.gtk3.app - INFO - software-center-agent finished with status 0
2012-03-07 13:44:27,318 - softwarecenter.backend.spawn_helper - WARNING - exit code 1 from helper for '['/usr/share/software-center/piston_generic_helper.py', '--datadir', '/usr/share/software-center/', 'SoftwareCenterRecommenderAPI', 'recommend_app', '{"pkgname": null}']'
2012-03-07 13:44:27,319 - softwarecenter.backend.spawn_helper - WARNING - got error from helper: 'ERROR:__main__:urclient_apps
Traceback (most recent call last):
  File "/usr/share/software-center/piston_generic_helper.py", line 194, in <module>
    piston_reply = f(**kwargs)
  File "/usr/lib/python2.7/dist-packages/piston_mini_client/validators.py", line 33, in wrapper
    "Argument '%s' must be a string" % varname)
ValidationException: Argument 'pkgname' must be a string
'
2012-03-07 13:44:27,319 - softwarecenter.db.categories - WARNING - Error while accessing the recommender service: ERROR:__main__:urclient_apps
Traceback (most recent call last):
  File "/usr/share/software-center/piston_generic_helper.py", line 194, in <module>
    piston_reply = f(**kwargs)
  File "/usr/lib/python2.7/dist-packages/piston_mini_client/validators.py", line 33, in wrapper
    "Argument '%s' must be a string" % varname)
ValidationException: Argument 'pkgname' must be a string

2012-03-07 13:44:27,319 - softwarecenter.ui.gtk3.widgets.recommendations - WARNING - Error while accessing the recommender agent for the details view recommendations: ERROR:__main__:urclient_apps
Traceback (most recent call last):
  File "/usr/share/software-center/piston_generic_helper.py", line 194, in <module>
    piston_reply = f(**kwargs)
  File "/usr/lib/python2.7/dist-packages/piston_mini_client/validators.py", line 33, in wrapper
    "Argument '%s' must be a string" % varname)
ValidationException: Argument 'pkgname' must be a string