I have an LDAP directory for the SAMBA account information only because I am running a MS Domain with a PDC and BDC located in different cities, connected by a VPN (openvpn).
For me that is the main advantage. I have not migrated to an ADS setup (waiting for SAMBA 4) and needed to have reasonable logon speeds at the second location. I also have the ldap replicated between both locations.
The SAMBA How guide that comes with samba list a few of the different requirements but the main one for a PDC and BDC was the use of an LDAP directory since the smbpasswd file or tdbsam was not replicated in samba between the two. Now it may be possible to use NFS to share the information but I don't think that there would be any db locking implemented and you may have problems.
for an example of the config files that I use.
Yes the bug is fixed. It turned out to be on the LDAP upgrade side.
Also the guide I use as the reference is "The Official SAMBA 3 HOWTO and reference guide available at www.samba.org
. The guide also has a good basic samba faultfinding section that should point you in the right direction. Also are you using XP or Vista on the clients? Or just using samba for *inx as well?
I am not sure about using PAM for samba and have not tried. When I found the part in the SAMBA how to about needing to use LDAP for the PDC and BDC I stopped looking at the rest.