public function storeCookie( $comment = null )
    {
        $userData = array();
        $sessionID = session_id();
        $currentUser = eZUser::currentUser();
        if( is_null( $comment ) )
        {
            if( $currentUser->isAnonymous() )
            {
                return '';
            }
            else
            {
                $userData[$sessionID] = array( 'email' => $currentUser->attribute( 'email' ),
                                               'name' => $currentUser->contentObject()->name() );
            }
        }
        else
        {
            $userData[$sessionID] = array( 'email' => $comment->attribute( 'email' ),
                                           'website' => $comment->attribute( 'url' ),
                                           'name' => $comment->attribute( 'name' ) );
            if ( !$currentUser->isAnonymous() )
            {
                $userData[$sessionID]['email'] = $currentUser->attribute( 'email' );
            }
        }
        setcookie( 'eZCommentsUserData', base64_encode( json_encode( $userData ) ), $this->expiryTime, '/' );
        return $userData;
    }