I updated my samba from 3.0 to 3.4 and now the ldap is having issues communicating to the samba, and vise versa.

when trying to login with:
smbclient -U user //mail.domain.com/user

I get the password prompt, but after I enter the password I get:

I've check ldap.conf, and my smb.conf, and both look in order...

What am I forgetting?