function opacity_get(obj){
	if(obj.style.opacity == undefined) return 1;
	return parseFloat(obj.style.opacity);
}


function opacity_set(obj, val){
	if(val < 0) val = 0;
	if(val > 1) val = 1;

	obj.style.opacity = val; 
	obj.style.MozOpacity = val; 
	obj.style.KhtmlOpacity = val; 
	val = Math.round(val * 100);
	obj.style.filter = "alpha(opacity=" + val + ")"; 
}