Talk:Face of Boe

I don't get how Captain Jack could be the Face of Boe. Like it says in this article, he mentions that Face of Boe, so therefore he must know about him. Also, he later says that he had the nickname, "The Face of Boe". But for some reason he doesn't realize this connection and realize that he is going to become the Face of Boe. How is this?? Is it just bad continuity?