Re: WordPress + bbPress Integration 101
based on my recollections, as i’m on a road trip and can’t readily pull up the code, WP2.6 (maybe older, too, i don’t know), in the midst of their new cookies, has an action hook that can be tapped at cookie-creation to make an additional cookie for bbPress to read (in my instance, bbPress is in /forums/ so the new cookie is restricted to that path). the function that destroys the cookies at logout doesn’t have an action hook, so it has to be overridden (it’s pluggable). on the bbPress end, it’s virtually identical–use an action hook at login to create the various cookies that WP expects, override the pluggable cookie-destroying function.
there’s also some work in syncing up all the various secrets.
it’s worth noting that the cookie that’s now restricted to wp-admin/ in WP2.6.x is the same cookie that was unrestricted in path previously, so the mechanics of the cookie contents and whatnot aren’t any different, just the path restrictions.