Problem mit Sleep/Wake des Devices

private void setupSleepDevice(int houre, int minute){
        Calendar calNow = Calendar.getInstance();
        Calendar calSet = (Calendar) calNow.clone();
        calSet.set(Calendar.HOUR_OF_DAY, houre);
        calSet.set(Calendar.MINUTE, minute);
        calSet.set(Calendar.SECOND, 0);
        calSet.set(Calendar.MILLISECOND, 0);
        if (calSet.compareTo(calNow) <= 0){
            calSet.add(Calendar.DATE, 1);
        }
        Intent intent = new Intent(getBaseContext(), SleepReceiver.class);
        PendingIntent pendingIntent = PendingIntent.getBroadcast(getBaseContext(), 0, intent, 0);
        alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
           alarmManager.setRepeating(AlarmManager.RTC,calSet.getTimeInMillis(),120000,pendingIntent);
    }
  // erzeugen eines Kalendertermines und damit verbundenen Intent an WakeReceiver zum entsperren des Devices
    private void setupWakeDevice(int houre, int minute){
        Calendar calNow = Calendar.getInstance();
        Calendar calSet = (Calendar) calNow.clone();
        calSet.set(Calendar.HOUR_OF_DAY, houre);
        calSet.set(Calendar.MINUTE, minute);
        calSet.set(Calendar.SECOND, 0);
        calSet.set(Calendar.MILLISECOND, 0);
        if (calSet.compareTo(calNow) <= 0){
            calSet.add(Calendar.DATE, 1);
        }
        Intent intent = new Intent(getBaseContext(), WakeReceiver.class);
        PendingIntent  pendingIntent = PendingIntent.getBroadcast(getBaseContext(), 0, intent, 0);
        alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);         
    alarmManager.setRepeating(AlarmManager.RTC_WAKEUP,calSet.getTimeInMillis(),120000,pendingIntent);
    }

public class SleepReceiver extends BroadcastReceiver {
    private Context context;


    @Override
    public void onReceive(Context k1, Intent k2) {
        // TODO Auto-generated method stub
        context = k1;
        Log.e(DataSource.class.getSimpleName(), "Device wird ins bett geschickt");
        //Toast.makeText(k1, "SleepAndLock", Toast.LENGTH_LONG).show();
        sleepAndLock();


    }


    private void sleepAndLock(){


        ComponentName devAdminReceiver; // this would have been declared in your class body
        // then in your onCreate
        DevicePolicyManager  mDPM = (DevicePolicyManager)context.getSystemService(Context.DEVICE_POLICY_SERVICE);
        devAdminReceiver = new ComponentName(context, SleepReceiver.class);


        boolean admin = mDPM.isAdminActive(devAdminReceiver);
        if (admin) mDPM.lockNow();
        else Toast.makeText(context, "no Admin", Toast.LENGTH_LONG).show();
    }
}

public class WakeReceiver extends BroadcastReceiver {
    private Context context;


    @Override
    public void onReceive(Context k1, Intent k2) {
        // TODO Auto-generated method stub
        context = k1;
        Log.e(DataSource.class.getSimpleName(), "Device wird aufgeweckt");
        wakeAndRelease();


    }


    private void wakeAndRelease(){
        PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
        PowerManager.WakeLock wakeLock = pm.newWakeLock((PowerManager.SCREEN_BRIGHT_WAKE_LOCK | PowerManager.FULL_WAKE_LOCK | PowerManager.ACQUIRE_CAUSES_WAKEUP), "TAG");
        wakeLock.acquire();
        KeyguardManager keyguardManager = (KeyguardManager) context.getSystemService(Context.KEYGUARD_SERVICE);
        KeyguardManager.KeyguardLock keyguardLock = keyguardManager.newKeyguardLock("TAG");
        keyguardLock.disableKeyguard();
    }
}