function openWindow(url, windowName, width, height)
{

 //center the popup window
 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;
  }
 }
 var xOffset = (xMax - width)/2, yOffset = (yMax - height)/2; 
 return (window.open(url, windowName ,'width='+width+',height='+height+',toolbar=no,scrollbars=no,resizable=no,screenX='+xOffset+',screenY='+yOffset+',top='+yOffset+',left='+xOffset));
}
function openWindowInBlank(url)
{
 width = 600;
 height = 400;
 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;
  }
 }
 var xOffset = (xMax - width)/2, yOffset = (yMax - height)/2; 
 return (window.open(url, '_blank' ,'width='+width+',height='+height+',toolbar=no,scrollbars=yes,resizable=yes,screenX='+xOffset+',screenY='+yOffset+',top='+yOffset+',left='+xOffset));
}