function createTzname() {
    $cnt = count( $this->tzname );
    if( 0 >= $cnt )
      return;
    $output = null;
    foreach( $this->tzname as $theName ) {
      $attributes = $this->_createParams( $theName['params'], array( 'LANGUAGE' ));
      $output    .= $this->_createElement( 'TZNAME', $attributes, $this->_strrep( $theName['value'] ));
    }
    return $output;
  }