Google is reporting “harmful code” on my site, but looks fine

(Note: I have not linked to my site, but you can see the
address below) Visiting my site gives that typical I have the
webpage listed under my Google Webmaster account, and it says:
Code: Problematic URLs on http://zeno.biyg.org/ Last checked / -
Details 1/2/12 /viewtopic.php?f=3t=45 - Details 1/4/12 I have
checked both those pages