function sameheight()
{
	var maxheight = Math.max(document.getElementById('left-content').offsetHeight,document.getElementById('main-content').offsetHeight,document.getElementById('right-content').offsetHeight);
	document.getElementById('left-content').style.height = maxheight + 'px';
	document.getElementById('main-content').style.height = maxheight + 'px';
	document.getElementById('right-content').style.height = maxheight + 'px';
}

function samelowheight()
{
	var maxheight = Math.min(document.getElementById('left-content').offsetHeight,document.getElementById('main-content').offsetHeight,document.getElementById('right-content').offsetHeight);
	document.getElementById('left-content').style.height = maxheight + 'px';
	document.getElementById('main-content').style.height = maxheight + 'px';
	document.getElementById('right-content').style.height = maxheight + 'px';
}

if(document.all)
{
	window.attachEvent('onload',sameheight);	
}
else
{
	window.addEventListener('load',sameheight,false);	
}