I don't recall putting my fake Alaska address with Entropay.
So I think I put my Aussie address in there.
It's your 2nd PSN account that you need to put the American address in.
Edit: I just checked my Entropay account, I put in my Australian address.
@Wingies, let me confirm:
You have a 2nd PS3 user account, with a different PSN account ... where you've entered in an American address?
You have an Entropay account, with an Australian address, linked to an Australian credit card?