if (document.images){

		enteron = new Image();
		enteron.src = "images/tour/enter-on.jpg";
		enteroff = new Image();
		enteroff.src = "images/tour/enter.jpg";

		exiton = new Image();
		exiton.src = "images/tour/exit-on.jpg";
		exitoff = new Image();
		exitoff.src = "images/tour/exit.jpg";
		
		continueon = new Image();
		continueon.src = "images/tour/continue-on.jpg";
		continueoff = new Image();
		continueoff.src = "images/tour/continue.jpg";
		
		joinon = new Image();
		joinon.src = "images/tour/join-on.jpg";
		joinoff = new Image();
		joinoff.src = "images/tour/join.jpg";

	}


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

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