[Veridiac]

I think I discovered my problem, I run vbDrupal, and drupal uses "user" php sessions, but mediawiki uses file, and apparently loading vbulletin's core stuff to get the authentication from the cookies will sometimes (but apparently not always...) cause drupal to start a session preventing mediawiki from opening the existing session (containing important edit tokens, etc)

Sooo for now I think I'm going to have to use a regular authentication plugin forcing users to sign in twice Nice work though, maybe eventually I'll track down what makes drupal start the session, or try again when I get around to upgrading vbdrupal.