function rollOn (image) {
	tempStr = image.src;
	tempArray = tempStr.split('.gif');
	image.src = tempArray[0]+ '_on.gif';
}

function rollOff (image) {
	tempStr = image.src;
	tempArray = tempStr.split('_on.gif');
	image.src = tempArray[0] + '.gif';
}

function loadRolls() {
  var i, a, as, image;
	image = new Image();
	as = document.getElementsByTagName("img");
  for(i=0; i < as.length; i++) {
		a = as[i];
    if(a.onmouseover) {
			tempStr = a.src;
			tempArray = tempStr.split('.gif');
			image.src = tempArray[0] + '_on.gif';
    }
  }
}