To start, I'm no expert, just a prospective applicant with too many opinions. 2 things:

1) Decide (regardless of language) is your supervisor going to be a stellar advocate of yours? Make sure he/she is the right person to be in your corner. Just make sure that your recommender understands the type of responses that you need in order to help your application.

2) Communicate with the adcoms - nearly all the top schools are falling over themselves over how internationally focussed they are - that means chances are they have access to translators. Plus, with all the international applicants - this cannot be a unique problem.

Refer to the instructions for recommendations for the schools you're applying to; every one I've looked at has addressed this issue, and if they don't it's worth a call or email to the admissions office. In general, what most schools request is that the recommender write the recommendation in their native language, and then have it professionally translated. They usually ask for both the original and the translated version. But this may vary by school, so it's best to check with each school you're applying to.

Send it in Chinese and see how the school reacts =).