I don't know if you are aware of this bug so I will try to describe it to you. You can duplicate items. Someone can knock you down with fists and then go to your inventory, when you wake up, he must still be in your inventory, then if you log off he can take all the stuff from your invetory and when you log in you still have your stuff and he does too...
I hope you can understand this is game breaking bug. ;)