var intervalId = null;    
function slideAd(id,nStayTime,sState,nMaxHth,nMinHth){    
  this.stayTime=nStayTime*1000 || 3000;    
  this.maxHeigth=nMaxHth || 450;    
  this.minHeigth=nMinHth || 2.5;    
  this.state=sState || "down" ;    
  var obj = document.getElementById(id);    
  if(intervalId != null)window.clearInterval(intervalId);    
  function openBox(){    
   var h = obj.offsetHeight;    
   obj.style.height = ((this.state == "down") ? (h + 10) : (h - 10))+"px";    
    if(obj.offsetHeight>this.maxHeigth){    
    window.clearInterval(intervalId);    
    intervalId=window.setInterval(closeBox,this.stayTime);    
    }    
    if (obj.offsetHeight<this.minHeigth){    
    window.clearInterval(intervalId);    
    obj.style.display="none";    
    }    
  }    
  function closeBox(){    
   slideAd(id,this.stayTime,"up",nMaxHth,nMinHth);    
  }    
  intervalId = window.setInterval(openBox,1);    
}