Occasionally the server will lose track of the client, and the client will continue doing things, but only client side. So you can be hit where your body actually is, and take damage without being reset, you can break blocks and the blocks will not drop a block. it's essentially "free cam" but on accident.
MC-2656
Occasionally the server will lose track of the client, and the client will continue doing things, but only client side.
Resolved
Duplicate
1
Duke Bammerfire
(Unassigned)
Unconfirmed
FreeCam, ghosting, server
Minecraft 1.4.2
Retrieved
I've had this same problem, its only on servers.
Just to be sure, is this the Problem your talking about: (see below link)
http://www.minecraftsurvivalgames.com/threads/1-3-game-ending-killing-glitch-bug.16114/
Short Description:
"All of a sudden everyone sees my player frozen but i can move but cant do anything and if i drop things they come out of my frozen player and my frozen player can attack from there but u will basically always die."
Also note: the glitch has been named the "Freecam Glitch". (this is not a mod)