function chgCSSClass(obj, cssName) {
  obj.className = cssName;
}

function addMenuROFX() {
  var mn = document.getElementById('menu');
  if (!mn) return true;
  var cs = mn.getElementsByTagName('td');
  if (!cs) return true;
  var c;
  for (var i = 0; i < cs.length; ++i) {
	c = cs[i];
	c.onmouseover = function() { chgCSSClass(this, 'over'); }
	c.onmouseout = function() { chgCSSClass(this, 'out'); }
  }
  return true;
}

function changeImage(myImg, myImgUrl) {
  var imgTag = document.getElementById(myImg);
  imgTag.src = myImgUrl;
}

function changeBackgroundImage(myImgUrl) {
  var tdTag = document.getElementById('homegraphiccell');
  tdTag.style.backgroundImage = 'url(' + myImgUrl + ')';
}