How to get iOS 6 maps in English?

I've just upgraded to iOS6, and need a bit of help to reset maps into English again.

I've set iOS for English/UK

In settings/Maps I've set Map Labels to be Always English

However, the street names are all in Thai characters (I'm in Bangkok this week), which must be great for local people, but useless for a traveller!

How can I set maps so that street names always appear in English, or at least, in Roman characters?

Am I going to have to go through this same pain in Hong Kong, Taipei, Tokyo, etc.?