PHP warning when importing configuration

This bug seems to be cause by the code in hierarchical_select.admin.inc line 187 to 191

There are two variables passed to the function hierarchical_select_admin_import but it's function signature only specifies one. The second variable contains the name of the configuration which can be used in the Description field e.g. this seems to work:

function hierarchical_select_admin_import($config_id, $formid) {                                                //ADD A SECOND VARIABLE TO THE FUNCTION <---------------------
  require_once(drupal_get_path('module', 'hierarchical_select') .'/includes/common.inc');

  drupal_add_css(drupal_get_path('module', 'hierarchical_select') .'/hierarchical_select.css');
  drupal_add_js('$(document).ready(function() { $(".hierarchical-select-code").focus(); });', 'inline');

  $form['config'] = array(
    '#type' => 'textarea',
    '#title' => t('Import Hierarchical Select configuration code'),
    '#cols' => 60,
    '#rows' => 15,
    '#description' => t('Copy and paste the results of an exported
      Hierarchical Select configuration here.<br />This will override the
      current Hierarchical Select configuration for %config_id.',
      array('%config_id' => $formid)                                                 //USE THAT VARIABLE FOR THE t() FUNCTION <------------------------------------------
    ),
    '#attributes' => array('class' => 'hierarchical-select-config-code'),
  );
  $form['interpreted_config'] = array('#type' => 'value', '#value' => NULL);
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t("Import"),
  );
  $form['#redirect'] = NULL;
  return $form;
}