How to set permissions on new files/folder

Hi,

I'm using mac os x server as SMB file sharing server and i got some issues with permissions.

I try to use POSIX permissions. I put :

owner -> read & write

group -> read & write

other -> read only

And after propagate these permissions it's working fine.

Until an user create a folder or a file and i see that the permissions of it are :

owner -> read & write

group -> read only

other -> read only

I have set default permissions on new files and folder for this sharepoint with the great permissions for the group. But it didn't work...

Someone have a solution ?