That actually helped! Thanks!
Looks like the schema was loaded because now i can see my domain in the administration interface. But i'm still getting these kinds of errors when i'm trying to create a posix group :
Code:
[LDAP: error code 65 - object class 'sambaGroupMapping' requires attribute 'sambaSID']
By my guess, looks like the schema is loaded but the directory wasnt modified according to the schema. If i remember correctly samba was supposed to make the entries into the directory, after restarting the service, no luck and no word about it in the logs.