[xwiki-users] XWiki and Kerberos SSO: authorization checks fail

Hello all, I'm trying to configure Kerberos SSO using AppServerTrustedAuthServiceImpl. I'm using latest xwiki, 1.8 rc 1 and to the contrary of what Admin Guide for Authentication states, this class is included in xwiki-core module. Nevertheless, I've configured application server well and set AppServerTrustedAuthServiceImpl to be used. Problem is that user authorization checks fail. In debug log I saw that user creation was started but auth_createuser context param was empty/null and thus not equal to string "empty" which createUser of XWikiAuthServiceImpl expects, so user wouldn't actually get created and thus when XWikiRightServiceImpl. To set auth_createuser parameter to "empty" I've adjusted xwiki.cfg by adding xwiki.authentication.createuser=empty. If this is what really has to be done, it would be good that Admin Guide gets updated with this information. After setting createuser to "empty", debug log changed but just a little bit (see attached log archive). Now it seems that user is being created but it still has no access rights. Does someone have any ideas how to configure this to work? Thanks in advance! Regards, Stevo.