function llamarasincrono(url, id_contenedor){
	var pagina_requerida = false
	if (window.XMLHttpRequest) {// Si es Mozilla, Safari etc
		pagina_requerida = new XMLHttpRequest()
	} else 
		if (window.ActiveXObject){ // pero si es IE
			try {
				pagina_requerida = new ActiveXObject("Msxml2.XMLHTTP")
				} 
			catch (e){ // en caso que sea una versión antigua
				try{
					pagina_requerida = new ActiveXObject("Microsoft.XMLHTTP")
					}
				catch (e){}
				}
			}
else
	return false
	pagina_requerida.onreadystatechange=function(){ // función de respuesta
		cargarpagina(pagina_requerida, id_contenedor)
	}
	pagina_requerida.open('GET', url, true) // asignamos los métodos open y send
	pagina_requerida.send(null)
	}

function cargarpagina(pagina_requerida, id_contenedor){
	if (pagina_requerida.readyState == 4 && (pagina_requerida.status==200 || window.location.href.indexOf("http")==-1))
	document.getElementById(id_contenedor).innerHTML=pagina_requerida.responseText
}

function sincroniza(url,id_contenedor){ 
	llamarasincrono(url,id_contenedor);
	}

function empezar() {
	initImage('contenedor');
}

function initImage(ventana) {
	image = document.getElementById(ventana);
	setOpacity(image, 0);
	image.style.visibility = "visible";
	fadeIn(ventana,0);
	actual=ventana;
}

function cerrarimagen(ventana) {
	fadeOut(ventana,100);
}

function fadeIn(objId,opacity) {
	if (document.getElementById) {
		obj = document.getElementById(objId);
		if (opacity <= 100) {
			setOpacity(obj, opacity);
			opacity += 10;
			window.setTimeout("fadeIn('"+objId+"',"+opacity+")", 50);
		}
	}
}

function fadeOut(objId,opacity){ 
	if (document.getElementById) {
		obj = document.getElementById(objId);
		if (opacity >=0) {
			setOpacity(obj, opacity);
			opacity -= 10;
			window.setTimeout("fadeOut('"+objId+"',"+opacity+")", 50);
		}
		else { obj.style.visibility = "hidden"; }
	}
}

function setOpacity(obj, opacity) {
	opacity = (opacity == 100)?99.999:opacity;
	// IE/Win
	obj.style.filter = "alpha(opacity:"+opacity+")";
	// Safari<1.2, Konqueror
	obj.style.KHTMLOpacity = opacity/100;
	// Older Mozilla and Firefox
	obj.style.MozOpacity = opacity/100;
	// Safari 1.2, newer Firefox and Mozilla, CSS3
	obj.style.opacity = opacity/100;
}

activateMenu = function(nav) {
	    if(document.all && document.getElementById(nav).currentStyle){
	        // only MSIE supports document.all
            var navroot = document.getElementById(nav);

            /* Get all the list items within the menu */
            var lis=navroot.getElementsByTagName("LI");
            for(i=0;i<lis.length;i++){
                /* If the LI has another menu level */
                if(lis[i].lastChild.tagName=="UL"){
                    /* assign the function to the LI */
                    lis[i].onmouseover=function(){
                        /* display the inner menu */
                        this.lastChild.style.display="block";
                    }
                    lis[i].onmouseout=function(){
                        this.lastChild.style.display="none";
                    }
                }
            }
        }
    }

function abrir_ventana(ventana,nombre,a,b,c,d) {
e="width="+a+","
f="height="+b+","
g="screenx="+c+","
h="screeny="+d+","
hola=window.open(ventana,nombre,e+f+g+h);
hola.focus()
}