How can I apply for L visa extension in Shanghai for my wife?

I am student and I have X visa from 15 Aug 2011. My wife has L visa from 15 Aug2011 untill 15 Nov 2011.

I want to extend her visa time duration, so I asked police at Shanghai and they said that we should prepare some evidences such as our marriage document (approved by the embassy of China at Iran) and a letter from my university that approve my study time.

Now, I sent my marriage document for embassy approving, but it will be ready after 15 Nov2011. What should I do?