This is quite visible for commentors and I thought I should share.
Call it lang_nl.inc.php and place it in UTF-8 folder of /plugins/serendipity_event_spamblock
(I run s9y v1.0)


<?php

/**
* @version $Revision: 1112 $
* @author Erwin Ravau <erwin at ravau dot net>
*/

@define('PLUGIN_EVENT ...