I have a Linux RH 4 server running Samba 3.0 with an OpenLDAP backend.
This server has been servicing Windows users from some time now. Most
of our developers are running Linux on their desktops and using local
accounts. Now I want Linux users to authenticate from the same
Samba/OpenLDAP as Windows users.

I have configured a Linux workstation to authenticate to Samba server
using Samba/Winbind. This appears to be working fine - thanks the
authconfig. However, my present challenge is how to get Linux users to
change their own passwords. It is possible to use smbpasswd to
change password without having to install Openldap on each Linux client
PC?

When I try to change my password on the Linux workstation using
smbpasswd, I get the following error message

Old SMB password:
New SMB password:
Retype new SMB password:
machine 127.0.0.1 rejected the (anonymous) password change: Error was :
No such user.
Failed to change password for

This error message suggests that smbpasswd is not using the
Samba/Openldap server for password changes.
How can I correct this?

My smb.conf file is listed below.

smb.conf
[global]
workgroup = WILLOW
server string = Mary Smith PC
security = domain
password server = 192.168.15.3
log file = /var/log/samba/%m.log
max log size = 50
socket options = TCP_NODELAY SO_RCVBUF=8192 SO_SNDBUF=8192
printcap name = /etc/printcap
dns proxy = No
idmap uid = 16777216-33554431
idmap gid = 16777216-33554431
cups options = raw
ldap passwd sync = yes
template shell = /bin/bash
winbind use default domain = yes
passwd chat debug = Yes