If "you" means me, the answer is no. I don't use SSO, so can't help.
If "you" means "someone on the forum", the answer is "wait and see".
One thing though. I may be completely wrong, but SSO is a generic term backed by various technologies (see
Wikipedia arcticle on SSO) and I don't think the SSO offered by auth_ldap has anything to do with SSO as offered by mod_auth_mellon. auth_ldap SSO is about kerberos/windows-AD, while mod_auth_mellon is about SAML. You can't mix both (I think). There exists a
SAML auth plugin for DokuWiki ; it's based on simpleSAMLphp though, not mod_auth_mellon.