function activateimg(whichimg)
{	var imgsrc = new String(document.getElementById(whichimg).src);
	imgsrc = imgsrc.replace(new RegExp('-off\.','g'),'-on\.');
	document.getElementById(whichimg).src = imgsrc;
}

function deactivateimg(whichimg)
{	var imgsrc = new String(document.getElementById(whichimg).src);
	imgsrc = imgsrc.replace(new RegExp('-on\.','g'),'-off\.');
	document.getElementById(whichimg).src = imgsrc;
}