usman@usmanPC:~$ software-center
2012-11-20 18:23:17,310 - softwarecenter.ui.gtk3.app - INFO - setting up proxy 'None'
2012-11-20 18:23:17,320 - softwarecenter.db.database - INFO - open() database: path=None use_axi=True use_agent=True
2012-11-20 18:23:17,671 - softwarecenter.backend.reviews - WARNING - Could not get usefulness from server, no username in config file
2012-11-20 18:23:17,868 - softwarecenter.ui.gtk3.app - INFO - show_available_packages: search_text is '', app is None.
2012-11-20 18:23:17,928 - softwarecenter.db.pkginfo_impl.aptcache - INFO - aptcache.open()
Segmentation fault (core dumped)