Q: AndroidActivity extends GameBaseActivity crashes I am having a class 

public class GameActivity extends Activity implements
  GLSurfaceView.Renderer, OnTouchListener{

The code does not have any problems, all needed methods are implemented. When I start the Activity it crashes with the following message:

java.lang.RuntimeException: Unable to instantiate activity
  ComponentInfo{[left out].GameActivity}:
  java.lang.ClassNotFoundException: Didn't find class "...GameActivity"
  on path [...]

I want to integreate the Google Game Service and Achievements in my game. Therefore I added the libary project and the GameBaseUtils as projects and also checkt that they should be exported inside my generated apk file. It compiles, the .jar for the google play services is also uploaded and will b e found. All includes are working. But when I start the game, it crashed immediately with the error message above. 
I followed the tutorials on developers.android.com https://developers.google.com/games/services/android/init
Can someone tell me what I am doing wrong? Here is my Manifest

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package=""
android:versionCode="1"
android:versionName="1.0" >

<uses-sdk
    android:minSdkVersion="8"
    android:targetSdkVersion="17" />

<!-- 
  Tell the market, that the the app requires at least OpenGLES 2.0 
  This is not really the truth but it will decrease the rate of error
 -->
<uses-feature android:glEsVersion="0x00020000" 
    android:required="true" />

<!-- Maybe not neccessary -->
<!-- <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.INTERNET"/> -->


<application 
    android:allowBackup="true"
    android:icon="@drawable/launcher_icon"
    android:label="@string/app_name"
    android:theme="@android:style/Theme.NoTitleBar.Fullscreen"
    android:screenOrientation="sensorLandscape" >

    <meta-data android:name="com.google.android.gms.games.APP_ID"
    android:value="13465798" />


    <activity
        android:name="GameActivity"
        android:screenOrientation="sensorLandscape">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <!-- For the implementation of Adds in this App -->
</application>

</manifest>


Edit: Locat output

07-21 01:13:47.730: W/dalvikvm(22578): Unable to resolve superclass of
  LGameActivity; (1182)  07-21 01:13:47.730:
  W/dalvikvm(22578): Link of class
  'L/GameActivity;' failed  07-21 01:13:47.730:
  D/AndroidRuntime(22578): Shutting down VM  07-21 01:13:47.730:
  W/dalvikvm(22578): threadid=1: thread exiting with uncaught exception
  (group=0x4159f930)  07-21 01:13:47.746: E/AndroidRuntime(22578): FATAL
  EXCEPTION: main  07-21 01:13:47.746: E/AndroidRuntime(22578):
  java.lang.RuntimeException: Unable to instantiate activity
  ComponentInfo{GameActivity}:
  java.lang.ClassNotFoundException: Didn't find class
  "GameActivity" on path:
  .apk  07-21 01:13:47.746:
  E/AndroidRuntime(22578):  at
  android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2106)
  07-21 01:13:47.746: E/AndroidRuntime(22578):  at
  android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
  07-21 01:13:47.746: E/AndroidRuntime(22578):  at
  android.app.ActivityThread.access$600(ActivityThread.java:141)  07-21
  01:13:47.746: E/AndroidRuntime(22578):    at
  android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234) 
  07-21 01:13:47.746: E/AndroidRuntime(22578):  at
  android.os.Handler.dispatchMessage(Handler.java:99)  07-21
  01:13:47.746: E/AndroidRuntime(22578):    at
  android.os.Looper.loop(Looper.java:137) 07-21 01:13:47.746:
  E/AndroidRuntime(22578):  at
  android.app.ActivityThread.main(ActivityThread.java:5041)  07-21
  01:13:47.746: E/AndroidRuntime(22578):    at
  java.lang.reflect.Method.invokeNative(Native Method)  07-21
  01:13:47.746: E/AndroidRuntime(22578):    at
  java.lang.reflect.Method.invoke(Method.java:511)  07-21 01:13:47.746:
  E/AndroidRuntime(22578):  at
  com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
  07-21 01:13:47.746: E/AndroidRuntime(22578):  at
  com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)  07-21
  01:13:47.746: E/AndroidRuntime(22578):    at
  dalvik.system.NativeStart.main(Native Method) 07-21 01:13:47.746:
  E/AndroidRuntime(22578): Caused by: java.lang.ClassNotFoundException:
  Didn't find class "GameActivity" on path:
  -1.apk  07-21 01:13:47.746:
  E/AndroidRuntime(22578):  at
  dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:65)
  07-21 01:13:47.746: E/AndroidRuntime(22578):  at
  java.lang.ClassLoader.loadClass(ClassLoader.java:501)  07-21
  01:13:47.746: E/AndroidRuntime(22578):    at
  java.lang.ClassLoader.loadClass(ClassLoader.java:461)  07-21
  01:13:47.746: E/AndroidRuntime(22578):    at
  android.app.Instrumentation.newActivity(Instrumentation.java:1054) 
  07-21 01:13:47.746: E/AndroidRuntime(22578):  at
  android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2097)
  07-21 01:13:47.746: E/AndroidRuntime(22578):  ... 11 more


A: I've found the error:
I had to mark both projects I am using for the app (GameBaseUtils and google-play-services_lib) as a libary project and add them to android libaries I want to use. The rest is handled by android on its own. 
