Preg_Replace with Links?

[AdamCap]

Here's the plugin I'm working on:

Product: vBulletin
Hook Location: postdata_presave
Order: 5

PHP Code:

$search[] = '/\b(Term1)\b/';
$replace[] = '<a href="http://somewhere.com/" class="some-class" target="_blank">$1</a>';

$this->post['pagetext'] = preg_replace($search, $replace, $this->post['pagetext'], 1); 


The replace works, however the HTML is just spit out and not parsed. I realize that BB code would work, but I need to style the link with CSS.

Any ideas on how to make this work?