title: Bad CPU type in executable
body: <p>I have to update an application for iOS, which is running from iOS 3.1.3 to the latest 5.1.</p>
  
  <p>When I build the code on the new Xcode 4.3.1 and try to test this app on an old device with iOS 3.1.3 I get an error "Bad CPU type on executable".</p>
  
  <pre><code>iOS Deployment Target = 3.1.3
  Architectures = armv6 $(ARCHS_STANDARD_32_BIT) - armv6 $
  Valid Architectures = armv6 armv7
  </code></pre>
  
  <p>If I add armv5 to the list of valid architectures, the code is installed on the device, but the application starts with a black screen and nothing happens.
  Then I can stop the program and start it on the device. It seems to be working then.</p>
  
  <p>Is it allowed to add armv5 to the list of valid architectures? Is this the solution to get rid of the error? </p>