var b1a = new Image();
                b1a.src = "../images/home-off.gif";
            	var b1b = new Image();
                b1b.src = "../images/home-on.gif";

				
				var b2a = new Image();
                b2a.src = "../images/news-off.gif";
            	var b2b = new Image();
                b2b.src = "../images/news-on.gif";

				
				var b3a = new Image();
                b3a.src = "../images/order-off.gif";
            	var b3b = new Image();
                b3b.src = "../images/order-on.gif";

				var b4a = new Image();
                b4a.src = "../images/news-off.gif";
            	var b4b = new Image();
                b4b.src = "../images/news-on.gif";

				var b5a = new Image();
                b5a.src = "../images/info-off.gif";
            	var b5b = new Image();
                b5b.src = "../images/info-on.gif";

				
				var b6a = new Image();
                b6a.src = "../images/links-off.gif";
            	var b6b = new Image();
                b6b.src = "../images/links-on.gif";
				
				var b7a = new Image();
                b7a.src = "../images/general.gif";
            	var b7b = new Image();
                b7b.src = "../images/general-on.gif";
				
				var b8a = new Image();
                b8a.src = "../images/disciplines.gif";
            	var b8b = new Image();
                b8b.src = "../images/disciplines-on.gif";

				var b9a = new Image();
                b9a.src = "../images/areastudies.gif";
            	var b9b = new Image();
                b9b.src = "../images/areastudies-on.gif";
				
				var b10a = new Image();
                b10a.src = "../images/series.gif";
            	var b10b = new Image();
                b10b.src = "../images/series-on.gif";
				
				var b11a = new Image();
                b11a.src = "../images/search-off.gif";
            	var b11b = new Image();
                b11b.src = "../images/search-on.gif";
				
				var actimg="b1"

				
                
              function act(imgName) {
                  document[imgName].src = eval(imgName + "b.src");
				  if (imgName != actimg) 
				  document[actimg].src = eval(actimg + "a.src");
              }

              function inact(imgName) {
                 document[imgName].src = eval(imgName + "a.src");
				 document[actimg].src = eval(actimg + "b.src");
	}
				function loadact(imgName){
				document[imgName].src = eval(imgName + "b.src");
				}