Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/aptdaemon/worker.py", line 963, in simulate
    status_path)
  File "/usr/lib/python2.7/dist-packages/aptdaemon/worker.py", line 1140, in _simulate_helper
    return depends, status, self._cache.required_download, \
  File "/usr/lib/python2.7/dist-packages/apt/cache.py", line 218, in required_download
    pm.get_archives(fetcher, self._list, self._records)
SystemError: E:I wasn't able to locate file for the libdb4.7-java-gcj package. This might mean you need to manually fix this package.