window.onload=init;
function init()
{
	if(!document.getElementById) return;
	else
	{
	
	var main = document.getElementById('main');
	var mainhaed = main.offsetHeight;
	
	var menu = document.getElementById('menu');
	var menuhaed = menu.offsetHeight;
	
	//dotid i menui
	var menuhaus =document.getElementById('menuhaus').offsetHeight;
	var menubotn = document.getElementById('menufotur').offsetHeight;
	
	var menuauka = menuhaus+menubotn;	

    // vidbot reiknud ut
    var x = mainhaed - menuauka;

    // er um ie ad raeda? http://mar.anomy.net/entry/2006/11/23/#h00.06.40
	var is_ie/*@cc_on = {
	version : parseFloat(navigator.appVersion.match(/MSIE (.+?);/)[1])
	}@*/;
	
	if(is_ie)
	{
	 x -= 7;
	}
	
	document.getElementById('menucontent').style.height=x+"px";
	}
	
}