function popup_center(a,b,w,h,scroll)
// a=endereco ; b=titulo
{	  		
	var winl = (screen.width-w)/2;
  var wint = (screen.height-h)/2;
	var settings  ='height='+h+',';
      settings +='width='+w+',';
      settings +='top='+wint+',';
      settings +='left='+winl+',';
      settings +='scrollbars='+scroll+',';
      settings +='resizable=no,';
			settings +='titlebar=no,';
      settings +='toolbar=no,';     
      settings +='location=no,';    
      settings +='directories=no,'; 
      settings +='status=yes,';  
			settings +='menubar=no';  
  NewWin2 = window.open(a,b,settings);
  if(parseInt(navigator.appVersion) >= 4){NewWin2.window.focus();}						
}