There is no Jake in the New Prophecy. I think you're thinking of Cody. :)
Plus Erin Hunter's got to be crazy if she named a girl Jake. Wait, is Jake a girl name too? --~~
I have met some girls named Cody, but not Jake. Still, who's to say that there aren't girls named Jake out there?
In Bluestar's Prophecy you meet Jake, he is Firestar and Scrourge's father. In the New Prophecy Jake does not appear, you must be thinking of Cody. (Cody is a kittypet she-cat.) You also meet Jake in the new book Tallstar's Revenge.