how to chase referrals automatically using ldap_search_ext_s?

[Chere Zhou <qzhou@isilon.com>]

I used ldap_set_option(connection, LDAP_OPT_REFERRALS, LDAP_OPT_ON) before 
doing the actual ldap_search_ext_s, but looking at network traces, it does 
not seem to happen.  What is the correct way to do this?

Thanks,
Chere