AsyncTask适用于Android 2.3.3,但不适用于ICS

我有tabactivity,每个标签都有ActivityGroup.在Forth Tab中,ForthActivityGroup有@L_4_3@myAsyncActivity类.在MyAsyncAcitivity中,我有这个代码.
我有这个 Android AsyncTask代码.调用doInBACkground(String .. params)并在Android 2.3.3上打印日志,但不在Android 4.0上打印.请SomeBody告诉我我的想法？

public class getXML extends AsyncTask<String,Integer,String>{
        private final ProgressDialog dialog = new ProgressDialog(this);

        @Override
        protected void onPreExecute() {
            this.dialog.set@R_262_8798@ge("Loading...");
            this.dialog.show();
        }

        @Override
        protected String doInBACkground(String... params) {
            Log.d("Payment","do BACkground");

            return "result";
        }

        @Override
        protected void onPostExecute(String result) {
            if (this.dialog.isShowing()) {
                this.dialog.dismiss();
            }

    }

AsyncTask task = new YourTask();
if (Build.VERSION.SDK_INT <= Build.VERSION_CODEs.GINGERBREAD_MR1) {
   task.execute(params);
} else {
   task.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR,params);
}