I would add carbohydrates. Post workout your muscle insulin sensitivity is greatly increased. Carbohydrates post workout will help replenish depleted glycogen stores and kick start the recovery process. Remember that in the gym your are actually BREAKING DOWN your muscles.
Post workout I would take:
60g whey isolate
40-80g of a easy digesting carbohydrate source such as waxy maize powder, oatmeal, plain rice cakes, white rice and/or fruit.
You could add BCAA to your post workout shake as well. BCAAs will also help with muscle recovery/repair.
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