if (empty($this->sql_search)) return $where;

        // convert from string to an associative array
        $fieldarray = where2array($this->sql_search, false, false);

	if (!empty($fieldarray['date_from']) OR !empty($fieldarray['date_to'])) {
	    $fieldarray['fecnac'] = rangeFromTo($fieldarray['date_from'], $fieldarray['date_to'], true);
	    unset($fieldarray['date_from']);
	    unset($fieldarray['date_to']);
	} // if
	
	$this->sql_search = array2where($fieldarray);