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

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


function swap_image(oriImage, nextImage) 
{
	if (document.images) 
	{
                eval("document." + oriImage + ".src='" + nextImage+ "'");
	}
}