Using Samba 3.0.13 (and I believe also 3.0.11 and 3.0.12) when I get a list of
account policies I see that the values "maximum password age" and "minimum
password age" are now called "maximum password age (seconds since 1970)" and
"minimum password age (seconds since 1970)". These two values, that in 3.0.9 had
the correct names (without the "seconds since 1970" part) cannot be read and set
anymore. 

If I try to get the value for "maximum password age" with the command
     
      pdbedit -P "maximum password age"

I get an error that says:

No account policy by that name
Account policy names are :
min password length
password history
user must logon to change password
maximum password age (seconds since 1970)
minimum password age (seconds since 1970)
lockout duration
reset count minutes
bad lockout attempt
disconnect time
refuse machine password change
       
If I try then to get the value for "maximum password age (seconds since 1970)"
with the command:

          pdbedit -P "maximum password age (seconds since 1970)"

I get an error that says:

account_policy_get: tdb_fetch_uint32 failed for field 4 (maximum password age
(seconds since 1970)), returning 0
valid account policy, but unable to fetch value!

I get quite the same error if I try to set the value instead of getting it, and
when I create a new user too, I suppose because creating a new user implies
readin the default policy values and adding them to the user's account record (I
use pdb as backend)

The same happens with "minimum password age" policy.