¿¿Special Announcement for closed threads??

[ZiNgA BuRgA]

Code:

<if $thread['closed'] then> Thread is closed you fool </if>

---

Probably won't work in header/headerinclude, but should work in showthread.
Add an additional and if you wish to exclude it specifically somewhere.

Note, I'm assuming you literally mean 'closed thread', as opposed to the user not having permission to post.