var gExtWind;
function fnExtWind(url,htpx,widpx){
var extWind;
var locationStr;
var htpx,widtx;
locationStr = url;
if ( htpx == "")
   { htpx = "HEIGHT = 600";}
else
   { htpx = "HEIGHT = " + htpx;}   
if ( widpx == "")
   { widpx = "WIDTH = 800";}   
else
   { widpx = "WIDTH =" + widpx;}
           
if (extWind)
   {
       extWind.focus();
       extWind.location = locationStr;
   }
   else
   {
   extWind = window.open(locationStr,"ExtWindow",htpx+","+widpx+" top=0,left=0,dependent,resizable=yes,alwaysRaised,menubar=yes,toolbar=yes,scrollbars=yes");
// this is to declare a global object variable so that the window can be closed using onunload function in the body tag
   gExtWind = extWind;
   extWind.focus();
   }

}