Swift_Mime_Headers_AbstractHeader::setLanguage PHP Method

For example, for US English, 'en-us'. This can be unspecified.

public setLanguage ( string $lang )
$lang	string

    public function setLanguage($lang)
    {
        $this->clearCachedValueIf($this->_lang != $lang);
        $this->_lang = $lang;
    }

Swift_Mime_Headers_AbstractHeader