function imageOn(img)
{
	var orgImgUrl = img.src.toLowerCase();
	if (orgImgUrl.indexOf("_on") < 0)
	{
		var pointPos = orgImgUrl.lastIndexOf(".");
		var newImgUrl = orgImgUrl.substring(0, pointPos) + "_On" + orgImgUrl.substring(pointPos, orgImgUrl.length);

		img.src = newImgUrl;
	}
}

function imageOff(img)
{
	var orgImgUrl = img.src.toLowerCase();
	if (orgImgUrl.indexOf("_on") >= 0)
	{
		var pointPos = orgImgUrl.lastIndexOf(".");
		var newImgUrl = orgImgUrl.substring(0, pointPos -3) + orgImgUrl.substring(pointPos, orgImgUrl.length);

		img.src = newImgUrl;
	}
}