How do you duplicate items in Pokemon Platinum?

from what i know, you can't. srry. :) but you might get lucky and find someone.

from: flyguy007

Hi this is flyman1111 i think you can duplicate items in Pokemon platinum all you have to do is get a ditto and a Pokemon with thief make sure the Pokemon with thief is holding the item you want to duplicate then you get into a double battle use thief on ditto and ditto will have the item that the Pokemon with thief has =] hope it has helped and worked