I've actually never heard that. People here usually say "Spain"! Once in Sevilla, though, I asked an old guy where I could find the bus to Cadiz, but since I learned Spanish from Latinos in NY, I said "Cadeece." He was baffled, and finally said, "Ah, Cadeethe!"
I can assure you, however, that Americans are perfectly able to say, "Nyah, nyah, nyah."