function setmargin(){
	 var p = document.getElementById("thumbnail").parentNode;
	 var t = document.getElementById("thumbnail");
	 if( t.currentStyle )
   {  
      var m = ((parseInt(p.currentStyle.width) - parseInt(t.currentStyle.width))/2)  + "px";
  }
   else if( document.defaultView.getComputedStyle )
   {
    var m = ((parseInt(getComputedStyle(p, '').width) - parseInt(getComputedStyle(t, '').width))/2) + "px";
   }
	 t.style.margin = "0 "+ m + " 0 " + m;
 	 //t.style.margin-right = m + "px";
}