[Samba] Group permissions not honoured by Windows clients

[Loris]

Hello, everybody.

I have a problem with group permissions.

On a Linux server (where I use Samba 3.0.28 under Fedora Core 8) there is the
"classical" share for home directories. And everything works just fine, as
always did, when I access my home directory from a Windows XP client.

In my home directory I have a symbolic link to another directory (that I do not
own, but for which I have (Linux) group write permissions (it's set to 770).
>From the Linux shell I can easily add files to and rename files in this 
directory.

But when I try to access the same directory from the Windows XP client, strange
things happen:

1) I can add files to the directory, but I cannot rename them.

2) When I use a Windows application, say Notepad, and try to save a new file in
that directory, I got a message saying "File already existent, do you want to
replace it?" (even if there's no file in the directory). If I answer yes, the
file is regularly written, but anyway I cannot rename it (as said in point 1).

I noticed that if I add write permissions for the directory for other users
(setting it to 772), everything works fine and I can do what I need. But I 
guess this shouldn't be the correct solution.

Seems like group write permissions are not honoured by Samba.

Any hint?

Thank you in advance,

        Loris