nss-pam-ldapd, a Name Service Switch (NSS) module and
Pluggable Authentication Module (PAM) that allows your
LDAP server to provide user account, group, host name,
alias, netgroup, and basically any other information that
you would normally get from /etc flat files or NIS. It also
allows you to do authentication to an LDAP server.

Key differences from nss_ldap:
* lighter NSS library
* lighter PAM library
* simpler internal semantics
* clear separation between NSS, PAM and LDAP code (the server
  part could easily be implemented in another language)
* less connections to the LDAP server

WWW: http://arthurdejong.org/nss-pam-ldapd/