[Samba] Shared drives not writeable

[Chris Nighswonger]

I am running Samba 3.6.6 on a Ubuntu 12.10 Samba domain member server.
Users are authenticated against a Samba DC running 3.6.9 over an LDAP
backend. I have a share configured as show below. Members of the
'staff-faculty' group can browse the share, but cannot write files to
any subdir for which they are not the owner. It appears that the only
reason they can read/traverse is because of o::r-x.

What I am looking for is a share where any member of the group may rw,
but the various users retain ownership of the files/dirs they create.

Here is what the perms, etc. look like:

drwxrwxr-x+   2 jdoe         staff-faculty 4.0K Jun  6 09:01 test

The acl looks like this:

# file: test
# owner: jdoe
# group: staff-faculty
user::rwx
group::rwx
group:staff-faculty:rwx
mask::rwx
other::r-x

I can post extended debug information, but thought perhaps there is an
obvious mistake in my share configuration and so am posting that
first.

Kind Regards,
Chris

-------------------

[Shared Drives]
    comment = Staff-Faculty Shares
    path = /netdrives/shared
    browsable = yes
    read only = no
    inherit acls = no
    inherit permissions = no
    create mask = 0771
    directory mask = 2771
    valid users = @"CAMPUS\staff-faculty"
    write list = @"CAMPUS\staff-faculty"
    admin users = @"CAMPUS\Domain Admins"