sudoers syntax

Hello, If I write in the sudoers file: jdd ALL=(ALL:ALL) NOPASSWD: ALL I can use any root command from my jdd account (through ssh). I would like to be only able to use "sudo -i" and I can't my goal is to be able to go full root if necessary, but not execute any other command to prevent environment (and others) problem how can I achieve this thanks jdd -- c'est quoi, usenet? http://www.dodin.org/wiki/pmwiki.php?n=Usenet.Usenet