Back button not working after displaying Contact
===

I am playing with the "Clickable List Items" code from Pro Android 4. The code is basically:

	public class MainActivity extends ListActivity implements OnItemClickListener
	{
	    @Override
	    public void onCreate(Bundle savedInstanceState)
	    {
	        super.onCreate(savedInstanceState);
	        
	        CursorLoader loader = new CursorLoader(this, Contacts.CONTENT_URI, null,
                null, null, Contacts.DISPLAY_NAME + " ASC");
	        Cursor cursor = loader.loadInBackground();
	        
	        String[] columns = new String[] { Contacts.DISPLAY_NAME };
	        int[] views = new int[] { android.R.id.text1 };
	        
	        SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, 
                android.R.layout.simple_list_item_1, cursor, columns, views, 
                    CursorAdapter.FLAG_REGISTER_CONTENT_OBSERVER);
	        setListAdapter(adapter);
	        
	        getListView().setOnItemClickListener(this);
	    }
	
		@Override
		public void onItemClick(AdapterView<?> adapterView, View view, int position, long id)
		{
			Uri contactUri = ContentUris.withAppendedId(Contacts.CONTENT_URI, id);
			Intent intent = new Intent(Intent.ACTION_VIEW, contactUri);
			startActivity(intent);
		}
	}

This all works fine. I see the list of contacts and when I tap a name it opens the address book for that person.

The problem is that the Back button does not work from the address book. According to the book , tapping the back button from the address book should bring me back to the above Activity. But instead I am taken back to the home screen.

My app is still running, when I switch to it manually I get back to it and the list view is at the proper previous scroll position, etc.

This is on Android 4.1.1. I'm wondering if there is something extra I should implement to make this work?
