function fixH(one,two){
	if (document.getElementById(one)){
		var lh=document.getElementById(one).offsetHeight;
		var rh=document.getElementById(two).offsetHeight;
		var nh = Math.max(lh, rh); 
		document.getElementById(one).style.height=nh+"px";
		document.getElementById(two).style.height=nh+"px";
	}
}

window.onload = function(){
	fixH('main_left','main_right');
}