if (document.images) {            // Active Images
            img1on = new Image();      
            img1on.src = "images/prof.gif"; 
            img2on = new Image(); 
            img2on.src = "images/konz.gif";  
            img3on = new Image();
            img3on.src = "images/gest.gif";
            img4on = new Image();
            img4on.src = "images/port.gif";      
            img5on = new Image();
            img5on.src = "images/kont.gif";
			img6on = new Image();
            img6on.src = "images/impr.gif";      
            img7on = new Image();
            img7on.src = "images/home.gif";
            img1off = new Image(); 
            img1off.src = "images/xx.gif";
         }

      // Function to 'activate' images.
         function imgOn(imgName) {
            if (document.images) {
               document.subnav.src = eval(imgName + "on.src");
            }
         }

      // Function to 'deactivate' images.
         function imgOff(imgName) {
            if (document.images) {
               document.subnav.src = eval(imgName + "off.src");
            }
         }