if (document.images){
	
	//top nav
	portfolioon = new Image();
	portfolioon.src = "images/topheader_port_on.gif";
	portfoliooff = new Image();
	portfoliooff.src = "images/topheader_port_off.gif";
	
	contacton = new Image();
	contacton.src = "images/topheader_cont_on.gif";
	contactoff = new Image();
	contactoff.src = "images/topheader_cont_off.gif";
	
	customon = new Image();
	customon.src = "images/topheader_cust_on.gif";
	customoff = new Image();
	customoff.src = "images/topheader_cust_off.gif";
	
	gifton = new Image();
	gifton.src = "images/topheader_gift_on.gif";
	giftoff = new Image();
	giftoff.src = "images/topheader_gift_off.gif";

	promoon = new Image();
	promoon.src = "images/promo_on.gif";
	promooff = new Image();
	promooff.src = "images/promo_off.gif";
	
	tellon = new Image();
	tellon.src = "images/topheader_tell_on.gif";
	telloff = new Image();
	telloff.src = "images/topheader_tell_off.gif";
	
	profileon = new Image();
	profileon.src = "images/topheader_prof_on.gif";
	profileoff = new Image();
	profileoff.src = "images/topheader_prof_off.gif";
	
	previouson = new Image();      
	previouson.src = "images/previous_on.gif"; 
	previousoff = new Image();      
	previousoff.src = "images/previous_off.gif";
	
	nexton = new Image();      
	nexton.src = "images/next_on.gif"; 
	nextoff = new Image();      
	nextoff.src = "images/next_off.gif";
	
	port1nav = new Image();
	port1nav.src = "images/portnav_1.gif";
	
	port2nav = new Image();
	port2nav.src = "images/portnav_2.gif";
	
	port3nav = new Image();
	port3nav.src = "images/portnav_3.gif";
	
}

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

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