[Samba] Windows Server 2012 can't join domain

[Jonis Maurin Ceará]

Hi.

I have 2 CentOS machines running both Samba4 using domain "sti.teste". I 
also have a third machine running Windows 2008 R2 on the same domain, 
everything working fine.
The problem is when i try to add a Windows 2012 Server to this 
domain.....i got this error on windows AD Domain Services Configuration 
Wizard (Prerequisites Check):
"Verification of prerequisites for Active Directory preparation failed. 
Unable to perform Exchange schema conflict check for domain sti.teste.
Exception: The RPC server is unavailable.
Adprep could not retrieve data from the server ad.sti.teste through 
Windows Managment Instrumentation (WMI).
[User Action]
Check the log file ADPrep.log in the 
C:\Windows\debug\adprep\logs\20130215160408-test directory for possible 
cause of failure."


Anyone got success on this setup, Win 2k12 server + S4?

Tks!