problem with utf8

[Hardkmel]

hi people,

i have a script :
<?
$num=0;
$backendURL = "http://rezo.net/backend/afp";

$limit = 1; // nombre maxi de news à afficher.

$file = fopen( $backendURL, "r");
if( $file ) {
$raw = fread( $file, 32000 );
fclose( $file );
if( eregi("<item>(.*)</item>", $raw, $rawitems ) ) {
$items = explode("<item>", $rawitems[0]);
$nb = count($items );

eregi("<title>(.*)</title>",$items[$num+1], $title);
eregi("<link>(.*)</link>",$items[$num+1], $link);

$tp2=$title[1];
$tp3=$link[1];
}
} else {
$tp2="Pas de news";
}

$tmp="info0_txt=".$tp2."&info0_lien=".$tp3;
$tmp=utf8_encode($tmp);
echo $tmp;

?>

But the text isn't encoded by $tmp=utf8_encode($tmp);
IF I retrieve data from a base (mysql) that 's work !! WHY ?!