Same inventory for every player when joining, can be used to duplicate

When any players join my multiplayer game on xbox beta 1.5.0.1 they get my inventory this is annoying as it duplicates all my items and they lose theirs we have found a work around where we out all their items in a chest before they leave and then when they join they will bin the items they get but it's very annoying and people may use this to duplicate, they will sometimes get their own inventory when joining and only usually happens after closing the game and reopening it or when I copy they world and go back onto it.