if (document.images) {
	register1on = new Image();
	register1on.src = "images/graphic_register_on.gif";

	register1off = new Image();
	register1off.src = "images/graphic_register.gif";

}

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

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