var g_oDisablePageLayer = null;
function DisablePage(sMessage,sImageSrc,oLayer)
{
  if (oLayer)
    g_oDisablePageLayer = oLayer;
  if (!oLayer && !g_oDisablePageLayer)
    {
      oLayer = document.createElement("TABLE");
      oBody = document.createElement("TBODY");
      oLayer.appendChild(oBody);
      oLayer.id = "DisablePageElem";
      oLayer.className = "DisablePageLayer";
      oLayer.border = 0;
      oLayer.cellSpacing = 0;
      oLayer.cellPadding = 0;
      var oRow = document.createElement("TR");
      oBody.appendChild(oRow);
      var oCell = document.createElement("TD");
      oRow.appendChild(oCell);
      oCell.align = "center";
      oCell.valign = "middle";
      oCell.innerHTML = "<span id=\"DisablePageMessage\"></span><br><img src=\"" +
                        (sImageSrc ? sImageSrc : "/cfr/images/VTS/progressbar.gif") + "\">";
      document.body.appendChild(oLayer);
      g_oDisablePageLayer = oLayer;
    }

  var iLeft = 0, iTop = 0, iWidth, iHeight;
  if (document.documentElement && document.documentElement.clientWidth > 0)
    {
      iLeft = document.documentElement.scrollLeft;
      iWidth = document.documentElement.clientWidth;
    }
  else
    iWidth = document.body.clientWidth;
  if (document.documentElement && document.documentElement.clientHeight > 0)
    {
      iTop = document.documentElement.scrollTop;
      iHeight = document.documentElement.clientHeight;
    }
  else
    iHeight = document.body.clientHeight;

  document.getElementById("DisablePageMessage").innerHTML = (sMessage ? sMessage : "Please wait...")
  g_oDisablePageLayer.style.top = iTop + "px";
  g_oDisablePageLayer.style.left = iLeft + "px";
  g_oDisablePageLayer.style.width = iWidth + "px";
  g_oDisablePageLayer.style.height = iHeight + "px";
  g_oDisablePageLayer.style.display = "";
  return oLayer;
}

function EnablePage()
{
  if (g_oDisablePageLayer)
    g_oDisablePageLayer.style.display = "none";
}