Comment 9 for bug 1373033

The relevant snippet from the installer debug log is:
Exception caught in process_line:
Traceback (most recent call last):
  File "/usr/lib/ubiquity/ubiquity/filteredcommand.py", line 145, in process_line
    return self.dbfilter.process_line()
  File "/usr/lib/ubiquity/ubiquity/debconffilter.py", line 287, in process_line
    if not input_widgets[0].run(priority, question):
  File "/usr/lib/ubiquity/plugins/ubi-console-setup.py", line 488, in run
    self.ui.set_keyboard(misc.utf8(self.db.get(question)))
  File "/usr/lib/ubiquity/ubiquity/plugin.py", line 48, in wrapper
    return target(self, *args, **kwargs)
  File "/usr/lib/ubiquity/plugins/ubi-console-setup.py", line 340, in set_keyboard
    ly = keyboard_names.layout_id(l, misc.utf8(layout))
  File "/usr/lib/ubiquity/ubiquity/keyboard_names.py", line 142, in layout_id
    return kn.layout_id(lang, value)
  File "/usr/lib/ubiquity/ubiquity/keyboard_names.py", line 90, in layout_id
    return self._layout_by_human[value]
KeyError: 'Deutsch'
Oct 1 10:57:06 ubiquity: ['log-output', '-t', 'ubiquity', '--pass-stdout', '/usr/lib/ubiquity/console-setup/keyboard-configuration.postinst', 'configure'] exited with code 141