function isShow(tab_id,div_id,t_Style)    //
{
   for(var i = 0;i < 4;i++)
   {
    document.getElementById("divs_"+i).style.display="none";
	  document.getElementById("tabs_"+i).style.backgroundImage='url(images/bt/bg_off.gif)';
	  document.getElementById("tabs_"+i).className="bgon";
   }
   document.getElementById(div_id).style.display=t_Style;
   document.getElementById(tab_id).style.backgroundImage='url(images/bt/bg_on.gif)';
   document.getElementById(tab_id).className="bgoff";
}

function setAClass(id,cls_name){
   if(document.getElementById(id)){
      document.getElementById(id).className=cls_name;	
   }
}