window.onload = rolloverInit;

function rolloverInit() {
	for (var i=0; i<document.images.length; i++) {
		if (document.images[i].parentNode.parentNode.tagName == "TD") {
			if (document.images[i].parentNode.tagName == "A") {
				setupRollover(document.images[i]);
			}
		}
	}
}

function setupRollover(thisImage) {
	if(thisImage.id != '') {
		thisImage.outImage = new Image();
		thisImage.outImage.src = thisImage.src;
		thisImage.onmouseout = rollOut;
	
		thisImage.overImage = new Image();
		thisImage.overImage.src = "/media/" + thisImage.id + "_on.gif";
		thisImage.onmouseover = rollOver;	
	}
}

function rollOver() {
	this.src = this.overImage.src;
}

function rollOut() {
	this.src = this.outImage.src;
}