I maintain the Korean IME (Input Method Editor) for Microsoft Windows and Office. Thus I work with Korean devs on a daily basis, Japanese devs regularly, and Chinese devs occasionally. We all code in C/C++.
I am most familiar with the code for the Korean IME. There are a few places with comments in Korean script (Hangul) where it is absolutely necessary, but even most comments are in English.
This may be because we are an international company, so we all need to communicate in a common language. Even emails are usually sent in English. However, when I verbally speak with my Korean co-workers, it’s almost always in Korean.
Although C/C++ reserved words are also “English” words, they have their own very specific meaning and end up becoming part of a language that isn’t even really “English,” per se.
edit: Incidentally, I was just listening to the stackoverflow podcast (#29, I think) where a similar question came up. Joel said the scripting language in Excel was localizable (reserved words changed to the local language.)