I have implemented multi-language support in my application using PHP's gettext() function. It's working correctly when testing at localhost, but on remote server there isn't any effect.

I'm using 000webhost that have gettext() support enabled, but when trying to change language there isn't any effect.

I have following file structure

.
+-- locale/
|   +-- en/
|       +-- LC_MESSAGES/
|           +-- messages.mo
|           +-- messages.po
|   +-- sv/
|       +-- LC_MESSAGES/
|           +-- messages.mo
|           +-- messages.po
+-- index.php

and I set language in index like this

if (isset($_GET['lang'])) {
    $lang = filter_var($_GET['lang']);

    switch ($lang) {
        case 'fi':
        case 'en':
        case 'sv':
            setcookie('lang', $lang);
            $_COOKIE['lang'] = $lang;
            break;
    }
}

// I18N support information here
$lang = (isset($_COOKIE['lang']) ? $_COOKIE['lang'] : 'fi');
putenv("LANG=" . $lang);
setlocale(LC_ALL, $lang);

// Set the text domain as "messages"
$domain = "messages";
bindtextdomain($domain, "locale");
bind_textdomain_codeset($domain, 'UTF-8');
textdomain($domain);

What would be the difference between localhost and remote server?

Thanks in advance.