Hello @ll, I installed this extension : http://www.mediawiki.org/wiki/Extension:PunBB_Authentication with a slightly different code : http://www.mediawiki.org/wiki/Extension_talk:PunBB_Authentication#mediawiki… It does work fine to let users from punbb connected into mediawiki. Only trouble : some of them have latin caracters (éèàçùêâû) in there login. Mediawiki use UTF-8 and PunBB ISO8859-1, so this is just a character encoding problem : I would like to do the equivalent as explained here for dokuwiki : http://wiki.splitbrain.org/wiki:auth:punbb#faq What has to be done ?