A lie is not saying something that is objectively untrue, but something that is untrue from the perspective of the speaker. If Pinocchio believes his nose will grow when he says that his nose will grow, then his nose will not grow, conversely, if he believes that his nose will not grow when he says this, than his nose will grow. So, if he says "this statement is a lie" with no expectations one way or the other, nothing will happen in response, not because he told the truth, but because he didn't say anything that he believed to be untrue. The whole "this statement is a lie" thing is just a word game, it's not related to anything but itself, not to some external fact that can be referred to, nor some internally held beliefs, essentially, he's saying nothing but nonsense.