var myWindowOpened = false;
var gt = Math.random();
var winName = 'CT' & gt;
function MM_openBrWindow(theURL,juNk,features) { 
  if(myWindowOpened) myWindowOpened.close();
  myfeatures = features + ',left=100,top=120';
  myWindowOpened = window.open(theURL,winName,myfeatures);
  myWindowOpened.focus();
}

function MM_closeBrWindow() { 
  if(myWindowOpened) myWindowOpened.close();
}