if (document.images) {
            var defImg = "button1join";
            var button1joinn = new Image();
            button1joinn.src = "images/button1join.jpg";
            var button1joinr = new Image();            
            button1joinr.src = "images/button1joinroll.jpg";            
            var button2joinn = new Image();
            button2joinn.src = "images/button2join.jpg";            
            var button2joinr = new Image();
            button2joinr.src = "images/button2joinroll.jpg";            
            var button3joinn = new Image();
            button3joinn.src = "images/button3join.jpg";
            var button3joinr = new Image();
            button3joinr.src = "images/button3joinroll.jpg";
            var button4joinn = new Image();
            button4joinn.src = "images/button4join.jpg";
            var button4joinr = new Image();
            button4joinr.src = "images/button4joinroll.jpg";
			var button5joinn = new Image();
            button5joinn.src = "images/button5join.jpg";
            var button5joinr = new Image();
            button5joinr.src = "images/button5joinroll.jpg";            
            var button6joinn = new Image();
            button6joinn.src = "images/button6join.jpg";            
            var button6joinr = new Image();
            button6joinr.src = "images/button6joinroll.jpg";
            var button1contributen = new Image();
            button1contributen.src = "images/button1contribute.jpg";            
            var button1contributer = new Image();
            button1contributer.src = "images/button1contributeroll.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");
        }