Can I get the users list straight from the system ?

Anybody know if (and how), I (since PostgreSQL) can get the users list from the linux-samba-winbind system in a box running into a GuinNT Domain ?

 

I mean: I have PostgreSQL in a linux-samba-windbind box which get the users list (ACL) from a GuinNT PDC.

 

Now, I need to use this "domain users list"  to grant permissions in PostgreSQL.

 

Is there any way to do it ??

 

Thanks in advance

 

Eduardo