function init_menu() {

    var lh=document.getElementById("zone_menu").offsetHeight;
	var rh=document.getElementById("zone2").offsetHeight;
	var nh = Math.max(lh, rh);
	document.getElementById("zone_menu").style.height=nh+"px";
	document.getElementById("zone2").style.height=nh+"px";

};

function addListener(element, type, expression, bubbling)
{
	bubbling = bubbling || false;
	
	if(window.addEventListener)	{ // Standard
		element.addEventListener(type, expression, bubbling);
		return true;
	} else if(window.attachEvent) { // IE
		element.attachEvent('on' + type, expression);
		return true;
	} else return false;
}
function removeListener(element, type, expression, bubbling)
{
	bubbling = bubbling || false;
	
	if(window.addEventListener)	{ // Standard
		element.removeEventListener(type, expression);
		return true;
	} else if(window.attachEvent) { // IE
		element.detachEvent('on' + type, expression);
		return true;
	} else return false;
}

addListener(window, 'load', init_menu)