function trim(s) 
{
	return s.replace(/^\s+|\s+$/g,'');
}

function add_event(type, fn)
{
    if (window.addEventListener){
        window.addEventListener(type, fn, '');
    } else if (window.attachEvent){
        window.attachEvent('on' + type, fn);
    }
}

function update_nav(obj, state, sel)
{
	if (!sel) {
		if (state) {
			obj.src = obj.src.replace('-unselected.jpg', '-rollover.jpg');	
		} else {
			obj.src = obj.src.replace('-rollover.jpg', '-unselected.jpg');	
		}
	}
}