title: Unrecognized selector sent to instance - on setter method
body: <p>Every time try to set the value of any variable in my model object, I receive 'Unrecognized selector sent to instance' error, and the app crashes. The ivars have been synthesized and they are not readonly. I have checked to see the values set are of the right type.</p>
  
  <p>I am not sure if it has to do with some connection in IB, which I have checked an re-checked. </p>
  
  <p>One extra bit of information: I started developing in an earlier version of Xcode, and the same piece of code used to work on that version.</p>
  
  <p>Here is the exact error message: </p>
  
  <pre><code>*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[NSCFString setDistance:]: unrecognized selector sent to instance 0x380ce50'
  2009-11-10 15:10:58.113 CabMeter[7432:207] Stack: (
      29303899,
      2457931593,
      29685819,
      29255286,
      29107906,
      11415,
      3140002,
      3149770,
      3199319,
      3236748,
      3170686,
      3230561,
      3179329,
      12452,
      3918761,
      3933474,
      4979284,
      4987529,
      3990121,
      2838067,
      2746396,
      2773173,
      37400273,
      29088640,
      29084744,
      37394317,
      37394514,
      2777091,
      9208,
      9062
  )
  </code></pre>