WordPress conflicting with phpBB session

I originally posted this on the phpBB forums but they said I should ask it here.1

Essentially what I have on my site is a WordPress page for news and a separate page for my phpBB3 forum (among other pages). I managed to make the phpBB login persist across all pages, but on the News (WordPress) page, the account details become “broken”.

This is what my custom account box looks like while logged in:

http://imgur.com/hW8I7

This is what it looks like only on the News page, still logged in:

http://imgur.com/6jiqi

What I’m ultimately trying to achieve is to allow people to use their phpBB login to comment on the WordPress articles.

This is the site in question: http://tgc.rggwebdesigns.com/