My app is ARC enabled with storyboarding and set to deployment target 5.1. If I change it to 4.2 deployment target so it will work on all devices I get the following errors:

I’m not sure what to do to fix this. thanks for any help
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The __weak directive is not available to iOS prior to 5.0. For < 5.0 versions you need to use __unsafe_unretained directive instead of __weak