title: Is it possible for a Facebook app to post a "private" Wall post that only the posting user and his/her friend can see?
body: <p>An app can post a wall post on a user's behalf.</p>
  
  <p>A user can post a wall post on his own Wall, tag a friend in it, then set it to only be seen by that friend.</p>
  
  <p>Can an app post a wall post on a user's Wall, tag a friend in it, and set it to only be seen by that friend?</p>