function mOver (imgName) {
	var currentImage = eval("window.document." + imgName);
	if (currentImage.src.search(/_on.gif/) == -1) {
		var num = currentImage.src.indexOf("_off.gif");
		currentImage.src = currentImage.src.slice (0, num) + "_over.gif";
	}
}

function mOut (imgName) {
	var currentImage = eval("window.document." + imgName);
	if (currentImage.src.search(/_on.gif/) == -1) {
		var num = currentImage.src.indexOf("_over.gif");
		currentImage.src = currentImage.src.slice (0, num) + "_off.gif";
	}
}