var NewWindow = "" 
function MM_openBrWindow(theURL,winName,features) { 
if ( NewWindow.focus){ 
NewWindow.close(); 
} 
NewWindow = window.open(theURL,winName,features); 
}





function MM_openBrWindow(theURL,winName,features) { //v2.0
  window.open(theURL,winName,features);
}