function adjustHeight() {
w_height = document.getSize().y;
s_height = document.getScrollSize().y;
// make sure the gray streaches as needed
if (w_height == s_height) {
  els = $$('table.gray_bk');
  if (els.length > 0) {
    els[0].setStyle('height', w_height - 145+'px');
  }
}
}