browserName = navigator.appName;
browserVer = parseInt(navigator.appVersion);
if ((browserName == "Netscape" && browserVer >= 3) || (browserName == "Microsoft Internet Explorer" && browserVer >=4)) version = "n3";
else version = "n2"
             if (version == "n3") {
             toc1on = new Image();
             toc1on.src = "../images/tocon_01.gif";
             toc2on = new Image();
             toc2on.src = "../images/tocon_02.gif";
             toc3on = new Image();
             toc3on.src = "../images/tocon_03.gif";
             toc4on = new Image();
             toc4on.src = "../images/tocon_04.gif";
             toc5on = new Image();
             toc5on.src = "../images/tocon_05.gif";
             toc6on = new Image();
             toc6on.src = "../images/tocon_06.gif";
             toc7on = new Image();
             toc7on.src = "../images/tocon_07.gif";
             toc8on = new Image();
             toc8on.src = "../images/tocon_08.gif";
             toc9on = new Image();
             toc9on.src = "../images/tocon_09.gif";
             toc10on = new Image();
             toc10on.src = "../images/tocon_10.gif";
             toc11on = new Image();
             toc11on.src = "../images/tocon_11.gif";
             toc12on = new Image();
             toc12on.src = "../images/tocon_12.gif";

			 
             toc1off = new Image();
             toc1off.src = "../images/tocoff_01.gif";
             toc2off = new Image();
             toc2off.src = "../images/tocoff_02.gif";
             toc3off = new Image();
             toc3off.src = "../images/tocoff_03.gif";
             toc4off = new Image();
             toc4off.src = "../images/tocoff_04.gif";
             toc5off = new Image();
             toc5off.src = "../images/tocoff_05.gif";
             toc6off = new Image();
             toc6off.src = "../images/tocoff_06.gif";
             toc7off = new Image();
             toc7off.src = "../images/tocoff_07.gif";
             toc8off = new Image();
             toc8off.src = "../images/tocoff_08.gif";
             toc9off = new Image();
             toc9off.src = "../images/tocoff_09.gif";
             toc10off = new Image();
             toc10off.src = "../images/tocoff_10.gif";
             toc11off = new Image();
             toc11off.src = "../images/tocoff_11.gif";
             toc12off = new Image();
             toc12off.src = "../images/tocoff_12.gif";

             }

     function img_act(imgName) {

             if (version == "n3") {
             imgOn = eval(imgName + "on.src");
             document [imgName].src = imgOn;
             }

     }

     function img_inact(imgName) {

             if (version == "n3") {
             imgOff = eval(imgName + "off.src");
             document [imgName].src = imgOff;
             }

     }