function ensureTop() {
	if (this != top) {
		top.location.href = this.location.href;
	}
}

function setImgVis(sImgField, sVis) {
	if (document.getElementById) {
		document.getElementById(sImgField).style.visibility = sVis;
	}
}

function chgImg(sImgObj,newImg) {
	if (document.images) {
		if (document.getElementById) {
			document.getElementById(sImgObj).src = newImg.src;
		} else {
			document[sImgObj].src = newImg.src;
		}
	}
}