[Samba] Manage user policy

[Kaspars]

 Hi all,

I interested in use Samba as PDC, but I want user account policy, that
users use password not less than 8 symbols and users must change their
password every 30 days... 
 I search trough google, try little reading of many manuals, but didn`t
find my answer... only what many people are interested in that too.
btw, some ppl say that it can be done with new samba-3 and ldap, how,
manuals?

thanks anyway,
Casper