[Samba] "password server" not working: 2.2.4

[Ken D'Ambrosio]

I've been having some trouble getting ACLs to work under my Samba 2.2.4
client (talking to my 2.2.4 "PDC").  Finally, I checked the log and
realized that it wasn't able to map SIDs to UID/GIDs.  Further checking,
and I realized that the client never made the request to the server. 
Here's some output from smbpasswd:

smbpasswd -D 4 fred
Initialising global parameters
params.c:pm_process() - Processing configuration file
"/usr/local/samba/lib/smb.conf"
Processing section "[global]"
doing parameter workgroup = XANOPTIX
doing parameter netbios name = freedom
handle_netbios_name: set global_myname to: FREEDOM
doing parameter server string = Samba Server
doing parameter password server = polaris       <-- PDC -is- listed...
doing parameter encrypt passwords = true
doing parameter security = DOMAIN
doing parameter log file = /usr/local/samba/var/log.%m
doing parameter max log size = 50
doing parameter local master = No
doing parameter domain master = False
doing parameter dns proxy = No
doing parameter printer admin = @ntadmin, kend, root
pm_process() returned Yes
New SMB password:
Retype new SMB password:
startsmbfilepwent_internal: unable to open file
/usr/local/samba/private/smbpasswd. Error was No such file or directory
unable to open passdb database.
Failed to find entry for user fred.
Failed to modify password entry for user fred

So, despite the fact that:
a) the PDC is explicitly listed (I've also tried "*") in the "password
   server" paramater, and
b) there is no "smb passwd file" heading,

it's still trying to go there.  Methinks this is a bug.  Clearly
something I've done has triggered it, though I'm not sure what.  If it's
of any help, this is also configured --with-acl-support for XFS.

Thanks for any info that could help me sort this out...

-Ken