php: file_get_contents encoding problem

Question

My task is simple: make a post request to translate.google.com and get the translation. In the following example I'm using the word "hello" to translate into russian.

header('Content-Type: text/plain; charset=utf-8');  // optional
error_reporting(E_ALL | E_STRICT);

$context = stream_context_create(array(
    'http' => array(
        'method' => 'POST',
        'header' => implode("\r\n", array(
            'Content-type: application/x-www-form-urlencoded',
            'Accept-Language: en-us,en;q=0.5', // optional
            'Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7' // optional
        )),
        'content' => http_build_query(array(
            'prev'  =>  '_t',
            'hl'    =>  'en',
            'ie'    =>  'UTF-8',
            'text'  =>  'hello',
            'sl'    =>  'en',
            'tl'    =>  'ru'
        ))
    )
));

$page = file_get_contents('http://translate.google.com/translate_t', false, $context);

require '../simplehtmldom/simple_html_dom.php';
$dom = str_get_html($page);
$translation = $dom->find('#result_box', 0)->plaintext;
echo $translation;

Lines marked as optional are those without which the output is the same. But I'm getting weird characters...

������

I tried

echo mb_convert_encoding($translation, 'UTF-8');

But I get

ÐÒÉ×ÅÔ

Does anybody know how to solve this problem?

UPDATE:

1. Forgot to mention that all my php files are encoded in UTF-8 without BOM
2. When i change the "to" language to "en", that is translate from english to english, it works ok.
3. I do not think the library I'm using is messing it up, because I tried to output the whole $page without passing it to the library functions.
4. I'm using PHP 5

Answer 1

Try to see this post if it can help CURL import character encoding problem

Also you can try this snippet (taken from php.net)

<?php
function file_get_contents_utf8($fn) {
     $content = file_get_contents($fn);
      return mb_convert_encoding($content, 'UTF-8',
          mb_detect_encoding($content, 'UTF-8, ISO-8859-1', true));
}
?>