var flag = false;

function imageload() {  // called with onLoad()
    if (document.images) {
		img0on = new Image(); img0on.src = "http://www.tableausoftware.com/img/gnav_home_on.gif";
        img1on = new Image(); img1on.src = "http://www.tableausoftware.com/img/subgnav_store_roll.gif";
        img2on = new Image(); img2on.src = "http://www.tableausoftware.com/img/subgnav_trial_roll.gif";
        img3on = new Image(); img3on.src = "http://www.tableausoftware.com/img/subgnav_contact_roll.gif";
        img4on = new Image(); img4on.src = "http://www.tableausoftware.com/img/storenav_home_on.gif";
        img5on = new Image(); img5on.src = "http://www.tableausoftware.com/img/gnav_products_on.gif";
        img6on = new Image(); img6on.src = "http://www.tableausoftware.com/img/gnav_customers_on.gif";
        img7on = new Image(); img7on.src = "http://www.tableausoftware.com/img/gnav_support_on.gif";
        img8on = new Image(); img8on.src = "http://www.tableausoftware.com/img/gnav_company_on.gif";
        img9on = new Image(); img9on.src = "http://www.tableausoftware.com/img/gnav_news_on.gif";
        img10on = new Image(); img10on.src = "http://www.tableausoftware.com/img/btn_tour_roll.gif";
        img11on = new Image(); img11on.src = "http://www.tableausoftware.com/img/storenav_cart_on.gif";
        img12on = new Image(); img12on.src = "http://www.tableausoftware.com/img/storenav_sign_on.gif";
        img13on = new Image(); img13on.src = "http://www.tableausoftware.com/img/storenav_account_on.gif";
        img14on = new Image(); img14on.src = "http://www.tableausoftware.com/img/btn_returntomain_roll.gif";
        img15on = new Image(); img15on.src = "http://www.tableausoftware.com/img/buynow_roll.gif";
        img16on = new Image(); img16on.src = "http://www.tableausoftware.com/img/btn_order_roll.gif";
        img17on = new Image(); img17on.src = "http://www.tableausoftware.com/img/btn_order_roll.gif";
        img18on = new Image(); img18on.src = "http://www.tableausoftware.com/img/prod_standard_roll.jpg";
        img19on = new Image(); img19on.src = "http://www.tableausoftware.com/img/prod_professional_roll.jpg";	
        img20on = new Image(); img20on.src = "http://www.tableausoftware.com/img/products_tour_roll.jpg";	
        img21on = new Image(); img21on.src = "http://www.tableausoftware.com/img/products_tour_roll.jpg";	
	img22on = new Image(); img22on.src = 'http://www.tableausoftware.comimg/btn_latest_roll.gif';
        return (flag = true);  // set the flag and let the function know know it can work
    }
}

if (document.images) {   // load the off images 
	img0off = new Image(); img0off.src  = "http://www.tableausoftware.com/img/gnav_home_off.gif";
	img1off = new Image(); img1off.src  = "http://www.tableausoftware.com/img/subgnav_store_off.gif";
	img2off = new Image(); img2off.src  = "http://www.tableausoftware.com/img/subgnav_trial_off.gif";
	img3off = new Image(); img3off.src  = "http://www.tableausoftware.com/img/subgnav_contact_off.gif";
	img4off = new Image(); img4off.src  = "http://www.tableausoftware.com/img/storenav_home_off.gif";
	img5off = new Image(); img5off.src  = "http://www.tableausoftware.com/img/gnav_products_off.gif";
	img6off = new Image(); img6off.src  = "http://www.tableausoftware.com/img/gnav_customers_off.gif";
	img7off = new Image(); img7off.src  = "http://www.tableausoftware.com/img/gnav_support_off.gif";
	img8off = new Image(); img8off.src  = "http://www.tableausoftware.com/img/gnav_company_off.gif";
	img9off = new Image(); img9off.src  = "http://www.tableausoftware.com/img/gnav_news_off.gif";
	img10off = new Image(); img10off.src  = "http://www.tableausoftware.com/img/btn_tour_off.gif";
	img11off = new Image(); img11off.src  = "http://www.tableausoftware.com/img/storenav_cart_off.gif";
	img12off = new Image(); img12off.src  = "http://www.tableausoftware.com/img/storenav_sign_off.gif";
	img13off = new Image(); img13off.src  = "http://www.tableausoftware.com/img/storenav_account_off.gif";
	img14off = new Image(); img14off.src  = "http://www.tableausoftware.com/img/btn_returntomain_off.gif";
	img15off = new Image(); img15off.src  = "http://www.tableausoftware.com/img/buynow_off.gif";
	img16off = new Image(); img16off.src  = "http://www.tableausoftware.com/img/btn_order_off.gif";
	img17off = new Image(); img17off.src  = "http://www.tableausoftware.com/img/btn_order_off.gif";	
	img18off = new Image(); img18off.src  = "http://www.tableausoftware.com/img/prod_standard_off.jpg";	
	img19off = new Image(); img19off.src  = "http://www.tableausoftware.com/img/prod_professional_off.jpg";	
	img20off = new Image(); img20off.src  = "http://www.tableausoftware.com/img/products_tour_off.jpg";
	img21off = new Image(); img21off.src  = "http://www.tableausoftware.com/img/products_tour_off.jpg";	
	img22off = new Image(); img22off.src = 'http://www.tableausoftware.comimg/btn_latest_off.gif';	
}


function rollin(imgName) {
    if (document.images && (flag == true)) {
        document[imgName].src = eval(imgName + "on.src");
    }
}

function rollout(imgName) {  // the normal onMouseOut function
    if (document.images){
        document[imgName].src = eval(imgName + "off.src");
    }
}