function imageOn(imgName) {
  if (document.images) {
  //alert('imgName:' + imgName);
  document.images[imgName].src = onImgArray[imgName].src;  //error here
  //document.images[imgName].src = "images/HomeButton4_on.jpg";
    }
  }
  
function imageOff(imgName) {
  if (document.images) {
  document.images[imgName].src = offImgArray[imgName].src;
    }
  }
  
 function setMsg(msg) {
   window.status = msg;
   return true; 
  } 
  
  //alert("Jill is testing");