title: Can’t build app with the Facebook SDK 3.1 on iOS 6
body: <p>I have integrated latest facebook sdk for ios 6 and configured it as done for previous ios version but it is giving me error that is listed below:</p>
  
  <pre><code>Undefined symbols for architecture i386:
    "_ACAccountTypeIdentifierFacebook", referenced from:
        +[FBSession renewSystemAuthorization] in FacebookSDK(FBSession.o)
    "_ACFacebookAppIdKey", referenced from:
        -[FBSession authorizeUsingSystemAccountStore:accountType:permissions:defaultAudience:isReauthorize:] in FacebookSDK(FBSession.o)
    "_ACFacebookAudienceEveryone", referenced from:
        -[FBSession authorizeUsingSystemAccountStore:accountType:permissions:defaultAudience:isReauthorize:] in FacebookSDK(FBSession.o)
    "_ACFacebookAudienceFriends", referenced from:
        -[FBSession authorizeUsingSystemAccountStore:accountType:permissions:defaultAudience:isReauthorize:] in FacebookSDK(FBSession.o)
    "_ACFacebookAudienceKey", referenced from:
        -[FBSession authorizeUsingSystemAccountStore:accountType:permissions:defaultAudience:isReauthorize:] in FacebookSDK(FBSession.o)
    "_ACFacebookAudienceOnlyMe", referenced from:
        -[FBSession authorizeUsingSystemAccountStore:accountType:permissions:defaultAudience:isReauthorize:] in FacebookSDK(FBSession.o)
    "_ACFacebookPermissionsKey", referenced from:
        -[FBSession authorizeUsingSystemAccountStore:accountType:permissions:defaultAudience:isReauthorize:] in FacebookSDK(FBSession.o)
    "_OBJC_CLASS_$_ACAccountStore", referenced from:
        objc-class-ref in FacebookSDK(FBSession.o)
    "_OBJC_CLASS_$_ASIdentifierManager", referenced from:
        objc-class-ref in FacebookSDK(FBSettings.o)
  ld: symbol(s) not found for architecture i386
  clang: error: linker command failed with exit code 1 (use -v to see invocation)
  </code></pre>
  
  <p>Can u tell what this means and how can I resolve this...?</p>