Problema con fwrite e array

[phpnew]

Ciao a tutti,
Ho un problema con la funzione fwrite, passandogli un array da scrivere.

Mi spiego, ho questo codice:

<?
include("config.inc.php");    
$Apri=fopen('config.inc.php', 'w');
$Scrivi=fwrite($Apri, '<?
define("upload_directory", "' . upload_directory . '");
define("full_path", "' . full_path . '");
$max_bytes=' . $max_bytes . ';
$max_files=' . $max_files . ';
$allowed_ext=' . $allowed_ext . ';
$allowed_ext_documents=' . $allowed_ext_documents . ';
$allowed_ext_markup=' . $allowed_ext_markup . ';
$allowed_ext_script=' . $allowed_ext_script . ';
$allowed_ext_sources=' . $allowed_ext_sources . ';
$allowed_ext_archives=' . $allowed_ext_archives . ';
$allowed_ext_executables=' . $allowed_ext_executables . ';
$allowed_ext_graphics=' . $allowed_ext_graphics . ';
$allowed_ext_audio=' . $allowed_ext_audio . ';
$allowed_ext_video=' . $allowed_ext_video . ';
$allowed_ext_others=' . $allowed_ext_others . '; 
$password="' . $password . '";
$Log="' . $Log . '";
$Log_error="' . $Log_error . '";
$Renomination="' . $Renomination . '";
$mail="' . $mail . '";
$address="' . $address . '";
$PasswordAdmin="' . $PasswordAdmin . '";
?>');
$Chiudi=fclose($Apri);

Le variabili che aggiungo quando scrivo nel file config.inc.php sono contenute nello stesso file che includo all'inizio della pagina, solo che da un file di partenza del genere:

<?
define("upload_directory", "./up/");
define("full_path", "http://ste95.no-ip.org/The Uploader/up/");
$max_bytes=1500*1024*1024;
$max_files=3;
$allowed_ext=array("zip", "rar", "jpg", "exe", "doc", "rtf", "htm", "html", "php", "js", "vb", "pinarolo", "zip", "rar", "exe", "com", "jpg", "png", "mp3", "wma", "avi", "vob", "ani", "sys", "txt");
$allowed_ext_documents=array("doc", "rtf", "txt");
$allowed_ext_markup=array("htm", "html");
$allowed_ext_script=array("php", "js");
$allowed_ext_sources=array("vb", "pinarolo");
$allowed_ext_archives=array("zip", "rar");
$allowed_ext_executables=array("exe", "com");
$allowed_ext_graphics=array("jpg", "png");
$allowed_ext_audio=array("mp3", "wma");
$allowed_ext_video=array("avi", "vob");
$allowed_ext_others=array("ani", "sys");
$password="301826e732d77bd72946e1443f2808ce";
$Log="true";
$Log_error="true";
$Renomination="false";
$mail="false";
$address="barone.dan@tiscali.it";
$PasswordAdmin="301826e732d77bd72946e1443f2808ce";
?>

Ottengo questa roba, in cui gli array vanno a farsi benedire:

<?
define("upload_directory", "./up/");
define("full_path", "http://ste95.no-ip.org/The Uploader/up/");
$max_bytes=1572864000;
$max_files=3;
$allowed_ext=1;
$allowed_ext_documents=Array;
$allowed_ext_markup=Array;
$allowed_ext_script=Array;
$allowed_ext_sources=Array;
$allowed_ext_archives=Array;
$allowed_ext_executables=Array;
$allowed_ext_graphics=Array;
$allowed_ext_audio=Array;
$allowed_ext_video=Array;
$allowed_ext_others=Array; 
$password="301826e732d77bd72946e1443f2808ce";
$Log="true";
$Log_error="true";
$Renomination="false";
$mail="false";
$address="barone.dan@tiscali.it";
$PasswordAdmin="301826e732d77bd72946e1443f2808ce";
?>