Move to wishlist

Question

How can I make the product only be copied in wishlist, when I click move to wishlist from basket. Because on default it remove from basket but I want my product to be added in wishlist and also to stay in basket. For moveing from wishlist to cart i have edited

app\code\core\Mage\Wishlist\controllers\IndexController.php on row 518 this piece of code from true to false

if ($item->addToCart($cart, false)) {
   $cart->save()->getQuote()->collectTotals();
}

but what about from cart to wishlist. I have tried to find something to CartControler.php but there is nothing that I can do.