Hello, I've a bukkit server (thanks to devs) and i've discovred recently that my players are using CJB mods on my server (infite items, life, give cmd, xray, etc...) How to block this types of client-side mods ? Really annoying... Thanks No-one knows how to do it ? EDIT by Moderator: merged posts, please use the edit button instead of double posting.
You'll also want http://forums.bukkit.org/threads/fix-sec-antihack-v1-8-blocks-bugs-cheats-and-hacks-818.9238/ together with what Zaros suggested!