public static function sendActivationEmail( $contentObject, $subscriber, $subscription )
    {
        $transport = eZNotificationTransport::instance( 'ezmail' );

        $email = $subscriber->attribute( 'email' );
        $tpl = eZTemplate::factory();
        $tpl->setVariable( 'contentobject', $contentObject );
        $tpl->setVariable( 'subscriber', $subscriber );
        $tpl->setVariable( 'subscription', $subscription );
        $mailSubject = $tpl->fetch( 'design:comment/notification_activation_subject.tpl' );
        $mailBody = $tpl->fetch( 'design:comment/notification_activation_body.tpl' );
        $parameters = array();
        $ezcommentsINI = eZINI::instance( 'ezcomments.ini' );
        $mailContentType = $ezcommentsINI->variable( 'NotificationSettings', 'ActivationMailContentType' );
        $parameters['from'] = $ezcommentsINI->variable( 'NotificationSettings', 'MailFrom' );
        $parameters['content_type'] = $mailContentType;

        $result = $transport->send( array( $email ), $mailSubject, $mailBody, null, $parameters );
        return $result;
    }