ldap auth does not works after openldap upgrade

[Leonardo Carneiro <chesterman86@gmail.com>]

Hello everyone,

I upgraded my debian machine from lenny to squeeze (the new stable)
that comes with samba 3.5.6 and openldap 2.4.23. this machines works
primarily as a PDC.

i have 3 services authenticating on ldap: samba, apache and redmine.
samba is acting very weird, but it's kinda working, but redmine and
apache aren't working at all.

these services do bind to the server, but it cannot find the users.
also, i cannot execute ldapsearchs via CLI. plus, in the bash, when i
try to change to some user other than root (eg: lscarneiro), the
system does not recognize the user:

fileserver:~# su - lscarneiro
I have no name!@fileserver:~$ whoami
whoami: cannot find name for user ID 1130

i'm very VERY noob on ldap and don't know exactly what kind of info i
should give to you guys to get some help. any help is very welcome