Restrict user to change group permission

[Reuben D. Budiardja]

Hello,
Is there a way to make any file and sub-directory under a directory is owned 
by a certain group, have permission 'rw' for that group by default, 
regardless who created the file and how the file was created, and restricted 
for any user to change the group permission (ie. I want the group permission 
to always be 'rw' so that even the user who created the file under that 
directory cannot change the group permission )

Thanks.

RDB
-- 
Reuben D. Budiardja
Dept. Physics and Astronomy
University of Tennesse, Knoxville, TN

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