sfHover = function() {
	var sfEls = document.getElementById("nav").getElementsByTagName("LI");
	for (var i=0; i<sfEls.length; i++) {
		sfEls[i].onmouseover=function() {
			this.className+=" sfhover";
			//se puede activar el hide y showboxes para internet explorer 6
			//si los menus desplegables se dibujan sobre select o sobre flash.
			//en el caso de flash, se puede usar el wmmode=transparent en lugar 
			//de apagarlo
			//hideSelectBoxes();
			//hideFlash();
		}
		sfEls[i].onmouseout=function() {
			this.className=this.className.replace(new RegExp(" sfhover\\b"), "");
			//showSelectBoxes();
			//showFlash()
		}
	}
}

function hideSelectBoxes(){
	var selects = document.getElementsByTagName("select");
	for (i = 0; i != selects.length; i++) {
		selects[i].style.visibility = "hidden";
	}
}
function showSelectBoxes(){
	var selects = document.getElementsByTagName("select");
	for (i = 0; i != selects.length; i++) {
		selects[i].style.visibility = "visible";
	}
}
function showFlash(){
	var flashObjects = document.getElementsByTagName("object");
	for (i = 0; i < flashObjects.length; i++) {
		flashObjects[i].style.visibility = "visible";
	}

	var flashEmbeds = document.getElementsByTagName("embed");
	for (i = 0; i < flashEmbeds.length; i++) {
		flashEmbeds[i].style.visibility = "visible";
	}
}


function hideFlash(){
	var flashObjects = document.getElementsByTagName("object");
	for (i = 0; i < flashObjects.length; i++) {
		flashObjects[i].style.visibility = "hidden";
	}

	var flashEmbeds = document.getElementsByTagName("embed");
	for (i = 0; i < flashEmbeds.length; i++) {
		flashEmbeds[i].style.visibility = "hidden";
	}

}
if (window.attachEvent) window.attachEvent("onload", sfHover);