Traceback (most recent call last):
  File "/usr/lib/python2.6/dist-packages/AppInstall/Menu.py", line 218, in _visible_filter
    self.itemIsInstalled(item):
  File "/usr/lib/python2.6/dist-packages/AppInstall/Menu.py", line 399, in itemIsInstalled
    return (self.cache.has_key(item.pkgname) and
AttributeError: 'NoneType' object has no attribute 'has_key'