// contribute button swap
if (document.images) {
            var defImg = "button1join";
            var button1joinn = new Image();
            button1joinn.src = "images/button1join.jpg";
            var button1joinr = new Image();
            button1joinr.src = "images/button1joinroll.jpg";
        }

        function act(imgName) {
            if (document.images)
                document[imgName].src = eval(imgName + "r.src");
        }

        function inact(imgName) {
            if (document.images)
                document[imgName].src = eval(imgName + "n.src");
        }