Permissions and access to data

Hi
Operating system Red Hat Enterprise 5.8, Data access Mac/PC environment on various OS levels. Access via smb

I am trying to set up a data shared area where a user group can read and write to its own directory, but can only write to another groups directory.

Example:
I have set up two volumes where the the owner/group can r/w/x but others can only write.

drwxrwx-wx 4 root group1 131072 Jun 7 13:21 STUDIO1
drwxrwx-wx 4 root group2 131072 Jun 7 13:21 STUDIO2

This seems to work but i am getting varying results from different "OS"
From OSX 10.7 i am getting the desired effect.
When logged in as group1 i can read and write to the Volume STUDIO1 and only write to STUDIO2. I also get prompted if a file of the same name already exists in volume STUDIO2, thus giving me the option to confirm a overwrite or not.

But this does not work the same way on various PC "OS" or on some mac "OS"

Questions i have is A: have i set up correctly. And B: is there a better way of setting up to get a more constant result across all the "OS"

thanks
Treds

permissions are correct and should work in a plain mac 10.8 or rhel environment ...

however, windows permissions work a little bit differently and may not recognize smb file permissions so i am not suprised if you are having issues coming from those boxes ... same issue with older mac versions though i am unclear when the mac os versions cut off to be more like unix ...

the fix? upgrade all client boxes to the most recent versions so it is easier to configure and/or troubleshoot ...