Hi,
That feature is not present Magento CE. (yes in EE)
If you plan write that feature from scratch.. you'll need modify all places where
the link -> add to wishlist is present...
Like product list page and detail product page.
In any case you should fetch all options for each producto and create a javascript function to achieve the final url ->http://xxx/wishlist/index/add/product/184416/
Tip: 184416 is the id of child product
Hope this help
Bye !