grazie per la risposta, pero' vedo che non cambia niente, ho messo il codice che mi hai dato tu
sul primo fotogramma chiave ho messo:
codice:
btn.onRelease=function(){ 
     read_external() 
} 

function read_external(){ 

     loader = new LoadVars(); 

     loader.onLoad = function(success) { 
           if(success){ 
                  if(this.ok){ 
                       reset_fields() 
                       j=1 
                       while(this["username"+j] != undefined){ 

                            _root.username.htmlText += this["username" + j]; 
                            _root.password.htmlText += this["password" + j]; 
                            _root.email.htmlText += this["email" + j]; 
                            _root.name.htmlText += this["name" + j]; 
                            _root.surname.htmlText += this["surname" + j]; 
                            _root.address.htmlText +=  this["address" + j]; 
                            _root.sesso.htmlText += this["sesso" + j]; 
                            _root.capelli.htmlText += this["capelli" + j]; 
                            _root.occhi.htmlText += this["occhi" + j]; 
                        j++ 
                      } 
                      _root.output.text = "ok"; 
                 }else{ 
                          reset_fileds() 
                 } 
           }else{ 
              trace("errore caricamento dati esterni: file flash-estrarre.php") 
           } 
      } 

     loader.load("flash-estrarre.php"); 
} 

function reset_fields(){ 
    _root.username.htmlText = ""; 
    _root.password.htmlText = ""; 
    _root.email.htmlText = ""; 
    _root.name.htmlText = ""; 
    _root.surname.htmlText = ""; 
    _root.address.htmlText = ""; 
    _root.sesso.htmlText = ""; 
    _root.capelli.htmlText = ""; 
    _root.occhi.htmlText = ""; 
}
sul pulsante con istanza btn, ho messo questo:
codice:
on(release){ read_external() }
nel file php flash-estrarre.php questo:
codice:
<?php

// dati per la connessione al database

$db_host = "localhost";
$db_user = "root";
$db_password = "";
$db_name = "login";

// connessione al database

$db = mysql_connect ($db_host, $db_user, $db_password);
$db_forum = mysql_select_db ($db_name, $db);

$query = "SELECT `username`, `password`, `email`, `name`, `surname`, `address`, `sesso`, `capelli`, `occhi` FROM `user` ORDER BY `name`";

$query_results = mysql_query($query);
$i = 0;

while($fetch = mysql_fetch_array($query_results))
     {
     $i++;
     echo "&username".$i."=".$fetch['username']."
";
     echo "&password".$i."=".$fetch['password']."
";
     echo "&email".$i."=".$fetch['email']."
";
     echo "&name".$i."=".$fetch['name']."
";
     echo "&surname".$i."=".$fetch['surname']."
";
     echo "&address".$i."=".$fetch['address']."
";
     echo "&sesso".$i."=".$fetch['sesso']."
";
     echo "&capelli".$i."=".$fetch['capelli']."
";
     echo "&occhi".$i."=".$fetch['occhi']."
";
     }

if($i)
  {
  echo "&i=".$i;
  echo "&ok=1";
  echo "&stop=1";
  }

else
   {
   echo "&ok=0";
   echo "&stop=1";
   }

?>