shell with sudo

[amir.fadaghi at equant.com]

All,

I am sort of new to sudo.  I am running a bunch of development servers that
I configure sudo on them.  I found the developers can run their script and
do some things as root by
sudo  user-script  shell.

My question is, how can I prevent users from getting to shell as root.  Any
help would be appreciated.
My /etc/sudores is as follows

root ALL = (ALL) ALL
trilogy ALL = (root) /usr/netscape/server4/https-ressundevl/start,
/usr/netscape/server4/https-ressund/stop,

Regards,