var oldThumb = "";
var oc = "";

function showImg(img, th)
{
	var thumb = document.getElementById(th);
	if (oldThumb != ""){
		oldThumb.className = "thumb";
		//oldThumb.src = oc;
	}
	oldThumb = thumb;
	thumb.className = "thumb-on";
	//oc = thumb.src;
	//thumb.src = thumb.src.replace("th_","th_on_");
	var target = document.getElementById("target");
	target.src = "images/empty.gif";
	target.src = img;
	//target.src = "images/gallery/summer/"+images_array[num]+".jpg";
}