It's getting stranger and stranger.
It seems it only fails when the following combination of characters exists in the topic, áfter the youtube video javascript call: [space][singlequote].
So, " '" breaks it, but " [b][/b]'" doesn't brake it.
The first "Hier 'n nieuw" doesn't brake it, and neither does the "foto's" part.
I've quadruple checked the source, and I cannot find any javascript call that is using the topic-content.
<font color="" face="Tahoma, Arial, Sans Serif" size="2"><span class="spnMessageText" id="msg">
Hier 'n nieuw filmpje van ons supervlot, tijdens de vlottenrace van de Regio Weert,
op vrijdagavond 23 mei jonstleden. <img src="images/PDT_Yellow_Sheika_03.gif" border="0"
alt="" title="" ALIGN=ABSBOTTOM /><br />
<div class="tube">
<script language="javascript">EmbedYT("http://www.youtube.com/v/m5u6vUKf8KY",375,298,"false","high","white","white")
</script>
</div><div class="break">
</div>
<br />Voor de foto's <a href="http://www.scoutbytes.com/gallery/vrexprw08/index.html" target="_blank">klik hier</a>.
<br /><table border="1" cellpadding="10" cellspacing="0" style="border-collapse: collapse" bordercolor="#000000">
<tr><td width="100%" bgcolor="#000000"><font color="beige"><span class="size1">
Het vorige bericht over de vlottenrace is door 'n onverlaat verwijderd, inclusief alle reacties.
</span class="size1"></font id="beige"></td></tr>
</table>
</div></span id="msg">
I do see I'm not closing the font tag....I'll check if that makes any difference.<