Linux Script Issue

I have  an error when I run the following command from a UNIX utility server, Our UNIX utility server has keys set up so we can run command on all UNIX/Linux servers in the environment.

Here is the error

# ssh linuxcna 'su - tadm -c "/etc/init.d/tmgr start"'
runuser: cannot set groups: Operation not permitted
[FAILED]

Now if I log into linuxcna and run the command, I still get an error :
# su - tadm -c "/etc/init.d/tmgr start"
runuser: cannot set groups: Operation not permitted
                                                                      [FAILED]

I also have the right permissions on /bin/su
# ls -l /bin/su
-rwsr-xr-x. 1 root root 32204 Oct 29 10:23 /bin/su

Any suggestions..