Event.observe(window,"load",function(){
    var maxheight = 0;
    if(document.all) { //This means it is IE
        if($('content_area') != null){
            var left_navigation = parseInt(document.getElementById('content_box').offsetHeight);
            var contentColumn = parseInt(document.getElementById('sidebar').offsetHeight);
            maxheight = (left_navigation>contentColumn)?(left_navigation):(contentColumn);
            maxheight = maxheight + 'px';
            var leftmaxheight = (parseInt(maxheight)) + 'px';
            $('content_box').setStyle({
                'height' : maxheight
            });
            $('sidebar').setStyle({
                'height' : leftmaxheight
            });
            var leftmaxheight1 = (parseInt(maxheight))-100+'px';
            $('sidebar1').setStyle({
                'height' : leftmaxheight1
            });
        }
    }
    else if($('content_area') != null){
        left_navigation = parseInt(document.getElementById('content_box').getStyle('height'));
        contentColumn = parseInt(document.getElementById('sidebar').getStyle('height'));
        maxheight = (left_navigation>contentColumn)?(left_navigation):(contentColumn);
        maxheight = maxheight + 'px';
        leftmaxheight = (parseInt(maxheight)) + 'px';
        $('content_box').setStyle({
            'height' : maxheight
        });
        $('sidebar').setStyle({
            'height' : leftmaxheight
        });
        leftmaxheight1 = (parseInt(maxheight))-100+'px';
        $('sidebar1').setStyle({
            'height' : leftmaxheight1
        });
    }
});