用于pt_BR的php pspell不起作用

I have installed pspell for en, es and pt_BR. ES and EN work just fine but pt_BR does not work.

PHPcode is:

$pspell = pspell_new("pt_BR", PSPELL_FAST);    
$sentence = "Oi, como voce llama-se";
$words = explode(" ", $sentence);

$output = ""; 
foreach($words as $word) {
    if (pspell_check($pspell, $word)) {
        // this word is fine; print as-is
        $output .= $word .  " ";
    } else {
        // this word is bad; look for suggestions
        $suggestions = pspell_suggest($pspell, $word);

        if (count($suggestions)) {
            $output .= current($suggestions). " ";
        } else {
            // no suggestions; just print the word
            $output .= '-'.$word;
        }
    }
}
echo $sentence . '<br/>'.$output;

The error message is:

Warning: pspell_new(): PSPELL couldn't open the dictionary. reason: No word lists can be found for the language "pt_BR". in /var/www/vhosts/httpdocs/_test.php on line 17 Warning: pspell_check(): 0 is not a PSPELL result index in /var/www/vhosts/httpdocs/_test.php on line 23 Warning: pspell_suggest(): 0 is not a PSPELL result index in /var/www/vhosts/httpdocs/_test.php on line 28 Warning: current() expects parameter 1 to be array, boolean given in /var/www/vhosts/httpdocs/_test.php on line 31 Warning: pspell_check(): 0 is not a PSPELL result index in /var/www/vhosts/httpdocs/_test.php on line 23 Warning: pspell_suggest(): 0 is not a PSPELL result index in /var/www/vhosts/httpdocs/_test.php on line 28 Warning: current() expects parameter 1 to be array, boolean given in /var/www/vhosts/httpdocs/_test.php on line 31 Warning: pspell_check(): 0 is not a PSPELL result index in /var/www/vhosts/httpdocs/_test.php on line 23 Warning: pspell_suggest(): 0 is not a PSPELL result index in /var/www/vhosts/httpdocs/_test.php on line 28 Warning: current() expects parameter 1 to be array, boolean given in /var/www/vhosts/httpdocs/_test.php on line 31 Warning: pspell_check(): 0 is not a PSPELL result index in /var/www/vhosts/httpdocs/_test.php on line 23 Warning: pspell_suggest(): 0 is not a PSPELL result index in /var/www/vhosts/httpdocs/_test.php on line 28 Warning: current() expects parameter 1 to be array, boolean given in /var/www/vhosts/httpdocs/_test.php on line 31 Warning: pspell_check(): 0 is not a PSPELL result index in /var/www/vhosts/httpdocs/_test.php on line 23 Warning: pspell_suggest(): 0 is not a PSPELL result index in /var/www/vhosts/httpdocs/_test.php on line 28 Warning: current() expects parameter 1 to be array, boolean given in /var/www/vhosts/httpdocs/_test.php on line 31 Oi, como voce llama-se

I checked that pt_BR is actually installed and working with the following command:

$ aspell -l pt_BR -a
@(#) International Ispell Version 3.1.20 (but really Aspell 0.60.7-20110707)
casa
+ casar

This is on Ubuntu 12.04.