on (release){
book_send = new LoadVars();
book_load = new LoadVars();
book.primoaccesso="si";
book.onLoad = function(success){
if(success){
idf=book_load.id;
_root.clp_contenuto.gotoAndPlay(3);
}
}
book_send.sendAndLoad("leggi.php", book_load, "POST");
}

prova così