function removeString(s, t) {

  i = s.indexOf(t);
  r = "";
  if (i == -1) return s;
  r += s.substring(0,i) + removeString(s.substring(i + t.length), t);
  return r;
  }

function AlternarImagen(img) {
	var searchString = '_on';
	var imgSrc = img.src.toLowerCase();
	var index = imgSrc.indexOf(searchString);

	if ( index > 0 ) {
      img.src = removeString(imgSrc, searchString);

      //img.src = imgSrc.substring(0,imgSrc.indexOf(searchString)) + remove(imgSrc.substring(i + searchString.length), searchString);
	} else {

	  var ext = imgSrc.substring(imgSrc.length-4, imgSrc.length );

      var leading = imgSrc.substring(0, imgSrc.length-4);

      var trailing = imgSrc.substring(imgSrc.length-4, imgSrc.length);

	  img.src = leading + searchString + trailing;
	}
}

var menuItems =
[

['Institucional',"http://www.ina.ac.cr/institucional/","","","","_self","0", , , , , ],
['Proveeduria',"http://www.ina.ac.cr/proveeduria/","","","","_self","0", , , , , ],
['Revista Tecnia',"http://www.ina.ac.cr/biblioteca/biblioteca_central/tecnia.html","","","","_self","0", , , , , ],
['INA Informa',"#","","","","_self","0", , , , , ],
['Contraloría de Servicios',"http://www.ina.ac.cr/Contraloria Serv/","","","","_self","0", , , , , ],
['Consulta de Carteles',"http://infoweb.ina.ac.cr/ConsultaCarteles/","","","","_self","0", , , , , ],


];