Strange behavior while running in Xcode: error only when "Development Build" is unchecked

My game runs smoothly on editor and on device (iPhone/iPod), but when I debug in Xcode I got EXC_BAD_ACCESS exceptions only if "Development Build" option in Build Settings of Unity is unchecked.

I don't understand what is the real effect of "Development Build" option in this scenario.

I got errors in Xcode even in handled exception inside a try/catch, but only if "Development Build" option is off.

Example:

 //NOTE: gL object is NULL and so the code will raise an exception
 
 void Start () 
 {
     try
     {
         GameLevel gL = ApplicationData.AllLevels.Find(delegate(GameLevel obj) {return obj.Level == 1000;}); // gL = null
         string test = gL.LevelName;
 
     }
     catch(Exception ex)
     {
         Debug.Log(ex.ToString());
     }
 }

In the console output as expected I have: System.NullReferenceException: Object reference not set to an instance of an object …

But when this code runs in Xcode debugger, with "Development Build" option unchecked, it seems like the exception simply is not handled and I got an EXC_BAD_ACCESS.

I highlight that this happens only when "Development Build" is unchecked.

Any idea about why this happens and how to avoid it?

I use Unity 4.3.4 and Xcode 5.1.1