e' forse sbagliata questa sintassi?

if (file_exists($uploadDirectory.$fileName)){

rename ("$uploadDirectory.$fileName", "$uploadDirectory.$fileName".rand(0,999999));

}

mi da:

Warning: rename(/Volumes/LAVORI/admin/imgUp/.paperino.jpg,/Volumes/LAVORI/admin/imgUp/.paperino.jpg247145): No such file or directory in /Volumes/LAVORI/admin/script/upload.php on line 15