java.lang.NoClassDefFoundError: android.os.AsyncTask

Weird error on Android 2.2 device . The following works in all devices and we never encountered this error until recently in GT-I5510 .Our app supports min sdk-level 8 .Clearing the app data from settings and starting the app fixed the issue but what i dont understand why its not able to find the class..Android support library is added . ``` java.lang.NoClassDefFoundError: android.os.AsyncTask at com.example.android.library.stTest.stController.runTests(stController.java:228) at com.example.android.myapp.Fragments.Connection.ConnectionFragment$1.run(ConnectionFragment.java:69) at android.os.Handler.handleCallback(Handler.java:587) at android.os.Handler.dispatchMessage(Handler.java:92) at android.os.Looper.loop(Looper.java:123) at android.app.ActivityThread.main(ActivityThread.java:4628) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:521) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:858) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616) at dalvik.system.NativeStart. //stController.java line is this pTest = new Test(context, this); //does an async task pTest.execute(pTestData); public class Test extends AbstractTest<TestData, Void, TestData> { private static final String LOG_TAG = Debug.LOG_TAG_+"Test"; private TestListener callback; // Invoking object that implements the callback listeners /** * Constructor * @param context * @param callback - the object that implements TestListener for the results. */ public Test(final Context context, final TestListener callback) { super(context); // Debug.v(LOG_TAG, "Constructor called."); this.callback = callback; } @Override protected TestData doInBackground(final TestData... args) { TestData TestData = args[0]; if (!isTestPossible()) { TestData.setTestState(TestState.FAILED_TO_RUN); } else { TestData.setLocalIpAddress(Utils.getLocalIpAddress()); try { TestData.setTestState(TestState.RUNNING); runTest(TestData); TestData.setTestState(TestState.FINISHED); } catch (Exception e) { Debug.e(LOG_TAG, "doInBackground(): runTest() exception: " + e); TestData.setTestState(TestState.FAILED_TO_RUN); } } return TestData; } @Override protected void onPostExecute(TestData results) { if (callback == null) { Debug.e(LOG_TAG, "onPostExecute(): listener callback is null!!"); } else { Debug.v(LOG_TAG, "onPostExecute() called. Results: " + results.toString()); callback.onTestComplete(results); callback = null; // Release reference to listener } } @Override protected void onCancelled(TestData results) { if (callback == null) { Debug.e(LOG_TAG, "onCancelled(results): listener callback is null!!"); } else { callback.onTestCancelled(results); callback = null; // Release reference to listener } } // This version is also needed for older OS. @Override protected void onCancelled() { if (callback == null) { Debug.e(LOG_TAG, "onCancelled(): listener callback is null!!"); } else { Debug.v(LOG_TAG, "onCancelled() called."); callback.onTestCancelled(null); callback = null; // Release reference to listener } } // C++ functions. // This function runs the actual test. private native void runTest(TestData TestData); } //Abstract Test public class AbstractTest <T1, T2, T3> extends AsyncTask<T1, T2, T3> { protected TelephonyManager teleMan; protected ConnectivityManager connMan; private Context testContext; public AbstractTest(final Context context) { teleMan = (TelephonyManager)context.getSystemService(Context.TELEPHONY_SERVICE); connMan = (ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE); testContext=context; } protected boolean isTestPossible() { if (!Utils.isNetworkAvailable(testContext)) { return false; } String localIpAddress = Utils.getLocalIpAddress(); if (localIpAddress == null || localIpAddress == "") { Debug.w(LOG_TAG, "isTestPossible(): no local IP address!!"); return false; } return true; } @Override protected T3 doInBackground(T1... params) { return null; } } ```