OK, here is how to re-create the problem had:
- Create a new project, using the Tab Bar Application
- Add a UILabel within SecondView.xib
- Add IBOutlet UILabel* myLabel; to FirstViewController.h
- Connect up myLabel in IB.
- Build and run.
When I click the second tab the app crashes with:
__TERMINATING_DUE_TO_UNCAUGHT_EXCEPTION__