Files group name changes when using co / ci

Hi
 
Trying RCS for the first time on named.conf.
 
xnormall the access is:
-rw-r-----   1 root     named       2877 Dec 28 20:13 named.conf
 
after creating the sub RCS directory (with w for the group), and running
ci named the RCS sub-directory contents are (note that root is now the
group:
-r--r-----   1 root     root        3066 Feb 13 20:38 named.conf,v
fred-ns05[root]:/chroot/named/etc/RCS# 
 
On checking out the file:
fred-ns05[root]:/chroot/named/etc# co -l named.conf
RCS/named.conf,v  -->  named.conf
revision 1.1 (locked)
done
fred-ns05[root]:/chroot/named/etc# ls -la
total 32
drwxr-xr-x   3 root     named        512 Feb 13 20:40 .
drwxr-xr-x   8 root     named        512 Oct 27 15:33 ..
-rw-r--r--   1 root     named       2598 Jul 30  2006 chroot-server.xml
-rw-r-----   1 root     root        2877 Feb 13 20:40 named.conf
 
Even if I use chgrp, or chown the files groupname changes.
 
How do I set it so that ci/co does not change the file's groupname?
 
Thanks
 
Bruce