  <!--
  function left_on(obj,id)
  {
	obj.src = '_img/left_button_' + id + '_on.png';
	obj.style.cursor = 'pointer';
  }

  function left_off(obj,id)
  {
	obj.src = '_img/left_button_' + id + '.png';
  }

  function main_on(obj,id)
  {
	obj.src = '_img/main_button_' + id + '_on.png';
	obj.style.cursor = 'pointer';
  }

  function main_off(obj,id)
  {
	obj.src = '_img/main_button_' + id + '.png';
  }

  function menu_click(url)
  {
	document.location.href=url;
  }
  -->