Clearing all Drupal cache doesn't clear htmlpurifier cache

Some module may provide a feature to "purge all caches." However, being that this module has it's own caching mechanism, this module does not get it's cache cleared upon running a function such as:

/**
 * Flush all caches or a specific one.
 *
 * @param $name
 *   (optional) Name of cache to flush.
 */
function admin_menu_flush_cache($name = NULL) {
  switch ($name) {
    case 'admin_menu':
      admin_menu_wipe();
      break;

    case 'cache':
      // Don't clear cache_form - in-progress form submissions may break.
      // Ordered so clearing the page cache will always be the last action.
      $core = array('cache', 'cache_block', 'cache_filter', 'cache_page');
      $cache_tables = array_merge(module_invoke_all('flush_caches'), $core);
      foreach ($cache_tables as $table) {
        cache_clear_all('*', $table, TRUE);
      }
      break;

    case 'menu':
      module_invoke('menu', 'rebuild');
      break;

    case 'requisites':
      // Change query-strings on css/js files to enforce reload for all users.
      _drupal_flush_css_js();

      drupal_clear_css_cache();
      drupal_clear_js_cache();
      break;

    case 'theme':
      module_invoke('system', 'theme_data');
      drupal_rebuild_theme_registry();
      break;

    default:
      // Flush all caches; no need to re-implement this.
      module_load_include('inc', 'system', 'system.admin');
      $form = $form_state = array();
      system_clear_cache_submit($form, $form_state);
      break;
  }
  drupal_goto();
}

Could the module be set to somehow respond to drupal's system_clear_cache($form, $form_state); function?