Actually I know I am right ... I cast people all the time for Print and TV, and it's considered a form of discrimination, like it or not ... and African Heritage is not the same as asking for Africans, and Caucasian is not a specific race.
What you do to get what you want is hire a good casting director who knows their stuff, they can get you a Japanese person without asking specifically for a Japanese person. They look at facial features, last names, etc. and narrow down your casting from their.
Well that's what I meant originally. That they were not looking for someone of Japanese heritage. I wasn't too concerned of the nitty gritty details.