function layoutColumns() {
    if (document.getElementById){
      var contentHeight = document.getElementById('centreCol').offsetHeight;
      var leftHeight = document.getElementById('leftCol').offsetHeight;

      if (contentHeight > leftHeight){
        newColHeight = contentHeight - 0;
        document.getElementById('leftCol').style.height=newColHeight+"px";
        document.getElementById('rightCol').style.height=newColHeight+"px";
      }
    }
  }