title: "This device isn't eligible for the requested build."
body: <p>I have an iPhone 3GS with 4.3 firmware. I downloaded a 3.1.3 firmware and was hoping to restore the iPhone using Organizer. But! I got the following error:</p>
  
  <p><b>"This device isn't eligible for the requested build."</b></p>
  
  <p>Any idea what's wrong?</p>