function resizesidebars()
       {
         var d = document.getElementById("bodyholder");
         var reqHeight = d.offsetHeight;
         
         document.getElementById('blockleft').style.height = reqHeight + "px";
         document.getElementById('blockright').style.height = reqHeight + "px";
         
         var navbar = document.getElementById("headernavplacement");
         navbar.style.visibility = "visible";
         
      }