Linux – Password expires 45 days even though ‘Password Must Change’ is set to ‘never’ (Samba+LDAP)

Since a few months ago Samba ask each of our users to change password at log on every 45 days (the default) and I have not been able to disable it. This setup had been running for 2 years before then without password expiration (as intended). I'm using Samba 3.4.7 + OpenLDAP 2.4.21 on Ubuntu 10.04-2 LTS

I found this page and follow the instructions:

http://playingwithsid.blogspot.com/2010/12/change-samba-password-expiry-setting.html

The default ‘Password Must Change’ policy was set to never and pdbedit/net sam shows ‘Password Must Change: never’ for each user, yet the passwords still get expire every 45 days.

I also checked LDAP too already. For the domain record, "sambaMaxPwdAge" is shown to be -1 as it should. For each user, "sambaPasswordCanChange" is 0, "sambaPasswordLastSet" is the correct password last changed time in epoch. There's no "sambaPasswordMustChange" for user records.

for /etc/smbldap-tools/smbldap.conf, the following line is commented out

@defaultMaxPasswordAge="45"

Can anyone help?