[Samba] Problem using pam_winbind to authenticate with Windows 2003 Active Directory Server.

[Wong, G. MR EECS]

We're trying to have AD Domain Users authenticate to AD server to login
to a Redhat Enterprise Linux AS (3.0) server.
Were running samba 3.06 on the Linux box.  We're using specifically
winbind and pam_winbind for this purpose.

I've followed all the instructions in the HOW-TO samba documentation on
setting up windbind, kerberos, and pam_winbind.

I've successfully logged into the LINUX box with certain AD user
credentials but not with others, which are the majority.

Here is what I've observed about the 2 sets of user accounts:

If sAMAaccountName = UserPrincipalName
  user can Log in
Else
  can't ( The error message from pam_winbind is:  PAM error was 10, NT
error was NT_STATUS_NO_SUCH_USER )

Why is this occuring?  Do I need to use other programs in conjunction
with samba to get this to work and if so are there
some instructions to do so?  HELP!