var popImg = null  
function openPopImg(picName, windowTitle, windowWidth, windowHeight)
{
  if (navigator.appName != "Microsoft Internet Explorer" 
      || parseInt(navigator.appVersion) >=4) 
    if(popImg != null) if(!popImg.closed)  popImg.close() 
	popImg= window.open('popupwindow.htm?img='+picName, windowTitle,"toolbar=no,scrollbars=no,resizable=no,left=100,top=100,width=" + 		(parseInt(windowWidth)+0)  + ",height=" + (parseInt(windowHeight)+0))
}