var TimeToFade = 500;

function fade(eid)
{
  var element = document.getElementById(eid);
  if (element == null)
  	return;
   
  if(element.FadeState == null)
  {
	if(element.style.opacity == null 
		|| element.style.opacity == '' 
		|| element.style.opacity == '1')
	{
	  element.FadeState = 2;
	}
	else
	{
	  element.FadeState = -2;
	}
  }
	
  if(element.FadeState == 1 || element.FadeState == -1)
  {
	element.FadeState = element.FadeState == 1 ? -1 : 1;
	element.FadeTimeLeft = TimeToFade - element.FadeTimeLeft;
  }
  else
  {
	element.FadeState = element.FadeState == 2 ? -1 : 1;
	element.FadeTimeLeft = TimeToFade;
	setTimeout("animateFade(" + new Date().getTime() 
		+ ",'" + eid + "')", 33);
  }
}

function animateFade(lastTick, eid)
{  
  var curTick = new Date().getTime();
  var elapsedTicks = curTick - lastTick;
  
  var element = document.getElementById(eid);
 
  if(element.FadeTimeLeft <= elapsedTicks)
  {
	element.style.opacity = element.FadeState == 1 ? '1' : '0';
	element.style.filter = 'alpha(opacity = ' 
		+ (element.FadeState == 1 ? '100' : '0') + ')';
	element.FadeState = element.FadeState == 1 ? 2 : -2;
	return;
  }
 
  element.FadeTimeLeft -= elapsedTicks;
  var newOpVal = element.FadeTimeLeft/TimeToFade;
  if(element.FadeState == 1)
	newOpVal = 1 - newOpVal;

  element.style.opacity = newOpVal;
  element.style.filter = 
	  'alpha(opacity = ' + (newOpVal*100) + ')';
  
  setTimeout("animateFade(" + curTick 
	  + ",'" + eid + "')", 33);
}