function GetObject(sName)
{
	var obj;
	if (document.getElementById)
	{
		obj = document.getElementById(sName);
	}
	else if (document.all)
	{
		obj = document.all[sName];
	}
	else if (document.layers)
	{
		obj = document.layers[sName];
	}
	return obj;
}

function init()
{
    window.onresize = ContentSize; 
    ContentSize();    
}

function ContentSize() 
{
  	var myHeight = 0;
  	
	if( typeof( window.innerWidth ) == 'number' ) 
	{
        //Non-IE
        myHeight = window.innerHeight;
    } 
    else if( document.documentElement && ( document.documentElement.clientWidth || document.documentElement.clientHeight ) ) 
    {
        //IE 6+ in 'standards compliant mode'
        myHeight = document.documentElement.clientHeight;
    } 
    else if( document.body && ( document.body.clientWidth || document.body.clientHeight ) ) 
    {
        //IE 4 compatible
        myHeight = document.body.clientHeight;
    }
    
    oHeader = GetObject("header");
    oNav = GetObject("nav");
    oContent = GetObject("content");
    oFooter = GetObject("footer");
        

    if ((oHeader.offsetHeight + oNav.offsetHeight + oContent.offsetHeight + oFooter.offsetHeight) < myHeight)
    {
	    oContent.style.height = (myHeight - oHeader.offsetHeight - oNav.offsetHeight - oFooter.offsetHeight) + "px";
	}
}