XF 1.3 Problem with statements?

I am using a statement to display adsense under the 1st posts in every thread, which is working fine.
However, I have ******* Support ticket plugin, and on any "Support Ticket" page, an adblock is being created under every single message and not the 1st post as shown below:

The code I am using before my adsense code is:
<xen:if is="{$post.position} % {$xenOptions.messagesPerPage} == 0 AND !{$message.conversation_id}">

Please help, thanks!