public function updateLanguageMask( $mask = false )
    {
        if ( $mask === false )
        {
            $locales = array();
            foreach ( $this->getTranslations() as $translation )
            {
                $locales[] = $translation->attribute( 'locale' );
            }

            $mask = eZContentLanguage::maskByLocale( $locales, $this->isAlwaysAvailable() );
        }

        $this->setAttribute( 'language_mask', $mask );
        $this->store();
    }