function SetOpacity(elem, opacityAsInt)
  {
      var opacityAsDecimal = opacityAsInt;
      
      if (opacityAsInt > 100)
          opacityAsInt = opacityAsDecimal = 100; 
      else if (opacityAsInt < 0)
          opacityAsInt = opacityAsDecimal = 0; 
      
     opacityAsDecimal /= 100;
     if (opacityAsInt < 1)
         opacityAsInt = 1; // IE7 bug, text smoothing cuts out if 0
     
     elem.style.opacity = (opacityAsDecimal);
	 elem.style.filter  = "alpha(opacity=" + opacityAsInt + ")";
 }

function FadeOpacity(elemId, fromOpacity, toOpacity, time, fps)
  {
      var steps = Math.ceil(fps * (time / 1000));
      var delta = (toOpacity - fromOpacity) / steps;
      
      FadeOpacityStep(elemId, 0, steps, fromOpacity, 
                      delta, (time / steps));
  }
  
 function FadeOpacityStep(elemId, stepNum, steps, fromOpacity, 
                          delta, timePerStep)
 {
     SetOpacity(document.getElementById(elemId), 
                Math.round(parseInt(fromOpacity) + (delta * stepNum)));
 
     if (stepNum < steps)
         setTimeout("FadeOpacityStep('" + elemId + "', " + (stepNum+1) 
                  + ", " + steps + ", " + fromOpacity + ", "
                  + delta + ", " + timePerStep + ");", 
                    timePerStep);
 }