[Samba] Problem with group/user permissions on write

[Nataniel Klug]

                Hello all,

                I am new to Samba and I am trying to make a configuration
that is not working and I am sure that’s me who don’t know what I am doing.
So the configuration I need is like this:

Groups: cnett, suporte
Users on group “cnett”: nata, anger
Users on group “suporte” ricardo, ariovaldo

                So now I have a share on /pub/bkp01 that has this
permissions:

drwxrwxr-x  3 root suporte 4096 2011-11-24 16:01 bkp01/

                Inside I need that users on group “suporte” can WRITE and
READ every file but they can only DELETE their own created
files/directories. The users on group “cnett” can have admin rights. So I
made this configuration on smb.conf:

[bkp01]
  comment = Backup01
  path = /pub/bkp01
  valid users = @suporte @cnett
  admin users = @cnett
  create mask = 0664
  directory mask = 0755
  writable = yes

                The problem is every user inside group “suporte” can DELETE
files/directories from other users in the same group.

                How can I solve this?

Regards,

Nataniel Klug