Preventing the change of root password

[pjoshi at parijat.info.com.np]

Hi Everybody,

I am new to the list and am sorry if this has been answered before.
I have given my sudo users the previlege to change the passwords. But in
that case they can also change the password of root. Is there a way, they
can be prevented from changing the root's password but at the same time be
able to change any other user's password.

Any help will be highly appreciated

Regards,
P Joshi.