title: iOS 4.0 v 4.2 AdMob Issue: Attempt to run on device breaks on ADBannerContentSizeIdentifierPortrait
body: <p>I am working on iOS app with Google AdMob SDK 3. The AdMob SDK contains the following code:</p>
  
  <pre><code>kADBannerContentSizeIdentifierPortrait =
      &amp;ADBannerContentSizeIdentifierPortrait != nil ?
      ADBannerContentSizeIdentifierPortrait :
      ADBannerContentSizeIdentifier320x50;
  </code></pre>
  
  <p>I understand that ADBannerContentSizeIdentifier320x50 is deprecated in iOS 4.2 and later. I need my app to be compatible down to iOS 4.0.</p>
  
  <p>When I build this code against iOS 4.0 SDK on the simulator, all goes fine. When I build against iOS 4.0 for device, I get the following error:</p>
  
  <pre><code>'ADBannerContentSizeIdentifierPortrait' undeclared
  </code></pre>
  
  <p>Why is this? I understand that AdMob implemented this code specifically to get around the issue of ADBannerContentSizeIdentifier320x50 being deprecated in favour of ADBannerContentSizeIdentifierPortrait.. so why doesn't it work? Any thoughts?</p>
  
  <p>Thanks.</p>