X-Threads 1.337 conflicts with Stefan T's WIKI plugin [SOLVED]

[ZiNgA BuRgA]

I just set up a clean MyBB 1.6.0, installed the Wiki, set a forum and user ID and then installed XThreads 1.337, created a normal user account, and I can create/edit articles in the wiki.

I can't see anything obvious that would prevent this happening.  The only thing coming to mind right now is if you've set a required field on the forum used for discussions, in which case, XThreads is requiring it to be filled in, but the Wiki won't fill it in.