title: Facebook symbols not found for i386 architecture
body: <p>I get the following error when trying to compile my project in xcode 4 (worked fine in xcode 3.x)</p>
  
  <pre><code>    Undefined symbols for architecture i386:
    "_OBJC_CLASS_$_FBSession", referenced from:
        objc-class-ref in View1Controls.o
    "_OBJC_CLASS_$_FBLoginDialog", referenced from:
        objc-class-ref in View1Controls.o
    "_OBJC_CLASS_$_FBRequest", referenced from:
        objc-class-ref in View1Controls.o
    "_OBJC_CLASS_$_FBStreamDialog", referenced from:
        objc-class-ref in View1Controls.o
  ld: symbol(s) not found for architecture i386
  collect2: ld returned 1 exit status
  </code></pre>
  
  <p>Can anyone explain whats wrong?  I'm sure I've correctly imported the header files..</p>
  
  <p>Thanks,</p>
  
  <p>Jack</p>