Android Gingerbread 2.3 Orientation Lock

Question

Currently my manifest is

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.itrack.enfora"
      android:versionCode="1"
      android:versionName="1.0"
      android:screenOrientation="portrait">
<uses-permission android:name="android.permission.SEND_SMS"></uses-permission>
<uses-permission android:name="android.permission.RECEIVE_SMS"></uses-permission>

<application android:icon="@drawable/icon" android:label="@string/app_name">
    <activity android:name=".EnforaSMS"
              android:label="@string/app_name">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>

</application>

But it's still not locked in portrait mode and rotations still happens. Anyone know if this is Gingerbread bug?