function CenterWindow (width, height){
  if (document.all)
    var xMax = screen.width, yMax = screen.height;
  else
    if (document.layers)
      var xMax = window.outerWidth, yMax = window.outerHeight;
    else
      var xMax = 640, yMax = 480;
      
  xOffset = (xMax - width)/2;
  yOffset = (yMax - height)/2;
}

function CenterWindowAndOpen (url, winName, width, height, param) {

  var w = window.open (url, winName, "width=" + width + ",height=" + height + "," param);
  return w;
}