Small coding issue?

[meeotch]

I don't know anything about php or message board software, so hopefully the way I'm describing this is correct or at least makes sense. It seems there's an error with the cookies that track all ready read threads in the announcements. If there's a new post in an announcement thread but I check a different thread in the forum I'm viewing first, when I get back to the forum, the "Jump to new post" button is gone and the "no new posts" icon is displayed.