guide_wnd = window.self ; // standby for very first launch :o)

var in_operation = "yes" ;

 function put_in_operation()
  {
    in_operation = "yes";
  }

 function launch_guide()
  {
   if ( (guide_wnd == self) || (guide_wnd.closed) ) {
    in_operation = "no" ;
    guide_wnd = window.open( "http://www.science.uva.nl/~rshulako/map.html", "map", "toolbar=no,location=no,status=no,resizable=no,width=540,height=120" ) ;
    // should of be enough for navigator window to open?
    self.setTimeout( 'put_in_operation()', 1200 ) ;
//    in_operation = "yes" ;
   }
   else
    guide_wnd.focus() ;
  } 

function days( year, month, day )
 {
  today = new Date();
  start = new Date( year, month-1, day );
  result = new Number( Math.floor((today.getTime() - start.getTime())/1000/60/60
/24) ) ;
  return "<FONT color='red'>Pending: " + result.toString() + " day(s)</FONT>" ;
 }