title: Xcode doesn't find openActiveSessionWithReadPermissions: FacebookSDK for iOS method
body: <p>I'm trying to upgrade the facebook sdk for iOS from 3.0 to 3.1.1. I've added the new FacebookSDK. I suppose that I did it correctly, it's easy... Installing the downloaded FacebookSDK-3.1.1.pkg and drag&amp;drop facebook.framework and FacebookSDKResources.bundle to the frameworks of the project.</p>
  
  <p>I'm trying to use openActiveSessionWithReadPermissions: method but when I build the project I get the message "No known class method for selector 'openActiveSessionWithReadPermissions:"</p>
  
  <p>I don't know why because if I check the FacebookSDK.framework headers I can see the openActiveSessionWithReadPermissions: in the FBSession.h class...</p>
  
  <p>I've cleaned the Build Folder, the derived data folder, the os x caches,...</p>
  
  <p>What is happening?</p>
  
  <p>Thanks a lot,</p>
  
  <p>Carlos</p>