Emmanuel Lecharny wrote:
for such generic LDAP question, I would redirect you to some good LDAP books :
http://www.amazon.com/LDAP-System-Administration-Gerald-Carter/dp/1565924916
or
http://www.amazon.com/Understanding-Deploying-LDAP-Directory-Services/dp/0672323168/ref=pd_sim_b_2/002-2562815-8009610
because the answer could be way to long by mail.
The search term "referral" should help. It is a general LDAP concept for
the requirement you describe, and it is supported (among others) by
ApacheDS.
See for instance here for a very brief explanation
http://ldapadministrator.com/resources/english/help/la331/ch05s05.html
or give Google a try (so did I for the link above).
Greetings from Nuremberg,
Stefan