title: ClassCastException on a subclass of ListFragment using compatibility library
body: <p><strong>This only happens when using the compatibility library for pre-3.0 devices</strong></p>
  
  <p>I'm getting an error that I cannot pin down. I have an Activity with a ListFragment and standard Fragment. It is just like the example provided in the Developers section of the Android Dev Guide.</p>
  
  <p><strong>ListFragment Subclass (no functions overridden)</strong></p>
  
  <pre><code>public class ItemListFragment extends ListFragment
  </code></pre>
  
  <p><strong>MainActivity</strong></p>
  
  <pre><code>public class ItemViewerActivity extends Activity {
      @Override
      public void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.item_viewer);
      }
  }
  </code></pre>
  
  <p><strong>Xml Layout for MainActivity</strong></p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="horizontal"&gt;
    &lt;fragment class="org.example.ItemListFragment"
      android:id="@+id/item_list_fragment"
      android:layout_width="0dp"
      android:layout_height="fill_parent"
      android:layout_weight="1" /&gt;
    &lt;FrameLayout
      android:id="@+id/item_info_frame"
      android:layout_width="0dp"
      android:layout_height="fill_parent"
      android:layout_weight="1" /&gt;
  &lt;/LinearLayout&gt;
  </code></pre>
  
  <p><strong>Error Message from LogCat</strong></p>
  
  <p>ERROR/AndroidRuntime: Caused by: java.lang.ClassCastException: org.example.ItemListFragment cannot be cast to android.app.Fragment</p>