function abrir(direccion,pantallacompleta,herramientas,direcciones,estado,barramenu,barrascroll,cambiatamano,ancho,alto,sustituir){
  var izquierda = (screen.availWidth - ancho) / 2;
  var arriba = (screen.availHeight - alto) / 2;
  var opciones = "fullscreen=" + pantallacompleta +
               ",toolbar=" + herramientas +
               ",location=" + direcciones +
               ",status=" + estado +
               ",menubar=" + barramenu +
               ",scrollbars=" + barrascroll +
               ",resizable=" + cambiatamano +
               ",width=" + ancho +
               ",height=" + alto +
               ",left=" + izquierda +
               ",top=" + arriba;
  var ventana = window.open(direccion,"ventana",opciones,sustituir);
}


function initMenu()
{
	var nodes = document.getElementById("main-nav").getElementsByTagName("li");
	for (var i=0; i<nodes.length; i++)
	{
		nodes[i].onmouseover = function()
		{
			this.className += " hover";
		}
		nodes[i].onmouseout = function()
		{
			this.className = this.className.replace(" hover", "");
		}
	}
}
if (document.all && !window.opera) attachEvent("onload", initMenu);

function initBrowser(){
	if (navigator.appVersion.indexOf("Safari") != -1) document.body.className += " safari";
}
if (window.addEventListener){
	window.addEventListener("load", initBrowser, false);
}

<!--
var now = new Date()
var Dia = new Array("Domingo", "Lunes", "Martes", "Mi&eacute;rcoles", "Jueves", "Viernes", "S&aacute;bado")
var Mes = new Array("January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December")
var Mes_esp = new Array("Enero", "Febrero", "Marzo", "Abril", "Mayo", "Junio", "Julio", "Agosto", "Septiembre", "Octubre", "Noviembre", "Diciembre")

var year = now.getYear()
var yearString = new String(year)
var LongYear = (year < 100 ? "19" : "20" ) + yearString.substring(yearString.length - 2)
var Hoy_esp =   Mes_esp[now.getMonth()] + " " +  now.getDate() +  " , " + LongYear
var Hoy =   Mes[now.getMonth()] + " " +  now.getDate() +  " , " + LongYear
// -->