@Lynne: It doesn't seem to work; the terms aren't being replaced, but I appreciate the suggestion!
postbit_display_start seems to work as far as getting the search/replace to work, but the links aren't parsed.
@HMBeaty: Sorry, I should have made it clearer:
I'm trying to link specific keywords within posts using preg_replace(). Full story: I run a Pokemon Card website, so I'm trying to automatically link card names to a database website so people can quickly look them up. I made a plugin for my WordPress portion of the site which works great, and I'm trying to port it over to vB.
I need to use CSS to style the links to make them look different than normal hyperlinks for convenience of my readers, so they can differentiate the types of links quickly.