title: How to know if a specific user has rated a Android App?
body: <p>In my android app i need implement a functionality that allow ask the user if he wish rate this app, if the response is "yes" i am going to redirect to androidmarket app, when the user already rated the app, the app shouldn't ask him for rate again. So i need any way to know if the user already has rated the app.</p>
  
  <p>I am using the android-market-api but i didn't find any method that return WHO rated
  my app.<br>
  The AppsRequest returns the global rating, for example : 5.<br>
  The CommentsRequest returns only comments but if there are some users that rate the app without comments the CommentsResponse  returns empty.<br>
  I need something like this:  </p>
  
  <p>app: myapp<br>
  user: jhonb78@gmail.com<br>
  rate: 3  </p>
  
  <p>Could you please give some ideas?</p>