if (navigator.appVersion.indexOf("2.") != -1){
        check = false;
        }
if ((navigator.appVersion.indexOf("3.") != -1) && (navigator.appName.indexOf("Explorer") != -1)){
        check = false;
        }
else {
        check = true;
        }

image1= new Image();
image1.src = "/site2/images/buttons/home_but_off.gif";
image1on = new Image();
image1on.src = "/site2/images/buttons/home_but_on.gif";

image2= new Image();
image2.src = "/site2/images/buttons/about_but_off.gif";
image2on = new Image();
image2on.src = "/site2/images/buttons/about_but_on.gif";

image3= new Image();
image3.src = "/site2/images/buttons/scheduling_but_off.gif";
image3on = new Image();
image3on.src = "/site2/images/buttons/scheduling_but_on.gif";

image4= new Image();
image4.src = "/site2/images/buttons/tutorial_but_off.gif";
image4on = new Image();
image4on.src = "/site2/images/buttons/tutorial_but_on.gif";

image5= new Image();
image5.src = "/site2/images/buttons/faq_but_off.gif";
image5on = new Image();
image5on.src = "/site2/images/buttons/faq_but_on.gif";

image6= new Image();
image6.src = "/site2/images/buttons/sitemap_but_off.gif";
image6on = new Image();
image6on.src = "/site2/images/buttons/sitemap_but_on.gif";

image7= new Image();
image7.src = "/site2/images/buttons/feedback_but_off.gif";
image7on = new Image();
image7on.src = "/site2/images/buttons/feedback_but_on.gif";

image8= new Image();
image8.src = "/site2/images/buttons/researchpubs_but_off.gif";
image8on = new Image();
image8on.src = "/site2/images/buttons/researchpubs_but_on.gif";

image9= new Image();
image9.src = "/site2/images/buttons/references_but_off.gif";
image9on = new Image();
image9on.src = "/site2/images/buttons/references_but_on.gif";

image10= new Image();
image10.src = "/site2/images/buttons/advisors_but_off.gif";
image10on = new Image();
image10on.src = "/site2/images/buttons/advisors_but_on.gif";

image11= new Image();
image11.src = "/site2/images/buttons/relatedsites_but_off.gif";
image11on = new Image();
image11on.src = "/site2/images/buttons/relatedsites_but_on.gif";

function imageon(name)   {
        document[name].src = eval(name + "on.src");
}
function imageoff(name)  {
        document[name].src = eval(name + ".src");
}
NN3 = true;

function on(name)  {
        if (check == true){
                imageon(name);}
}
function off(name)  {
        if (check == true){
                imageoff(name);}
}

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