[CentOS] Linux authentication like Ms Active Directory

Hi My People,

I am looking for the best tool or method for Linux authentication like Ms
Active Directory:

Scenarios 

1. Samba PDC for Linux Clients and Windows Xp 
	Status: (Server Centos OS 4.3 Samba 3.023 Setup Ready, Windows
Clients 			Ready can logon, Linux Clients Centos 4.3,
Ubuntus 6,06 			and Suse 10. Fail to logon error:
			Utils/net_rpc_join.c:net_rpc_join_newstyle(295)
			Error setting trust account password:
NT_STATUS_ACCESS_DENIED
			Unable to join domain mydomain.com.ve

2. Samba PDC with Ldap
	Comments about.

3. Samba with Fedora Directory
			Status: (The Same) I will revise it because show
easy talk 			with Ms Active Directory, I 	have already
setup Fedora 			Directory and I will join samba with it.

4. Your recommendations 

So really we want logon our linux clients in our linux PDC.    

Best regards

Jose Perales
Grid Systems