When I save the module admin page I get this:
Notice: Undefined index: view modes in field_view_mode_settings() (line 627 of /home/www2/drupal-7.16/modules/field/field.module).
Warning: Invalid argument supplied for foreach() in field_view_mode_settings() (line 627 of /home/www2/drupal-7.16/modules/field/field.module).