I've needed to configure LDAP authentication for Joomla! and the only way to get it to work together (with LDAP group based was by using groupOfUniqueNames, not the posixGroup. In other words, Joomla expects LDAP to follow the RFC2307bis schema.
This beg the question: do other LDAP using applications understand the RFC2307bis schema?
From what I could find, the 4 most important applications do:
Besides that, what is the state of general support for this schema (Apache auth, squid, groupware suites, freeradius)?
Any problems with such configuration (rfc2307bis, pam_ldap, nss_ldap and samba)?