Traceback (most recent call last):
  File "/usr/lib/ubiquity/ubiquity/frontend/gtk_ui.py", line 736, in <lambda>
    lambda: self.dbfilter.start(auto_process=True))
  File "/usr/lib/ubiquity/ubiquity/filteredcommand.py", line 123, in start
    self.dbfilter.start(self.command, blocking=False, extra_env=env)
  File "/usr/lib/ubiquity/ubiquity/debconffilter.py", line 217, in start
    preexec_fn=subprocess_setup, universal_newlines=True)
  File "/usr/lib/python3.2/subprocess.py", line 745, in __init__
    restore_signals, start_new_session)
  File "/usr/lib/python3.2/subprocess.py", line 1207, in _execute_child
    restore_signals, start_new_session, preexec_fn)
TypeError: Can't convert 'list' object to str implicitly