[SOLVED] Error inflating class android.support.v4.view.ViewPager

I've been trying to create a Pager for my application that runs on <uses-sdk android:minSdkVersion="10" android:targetSdkVersion="15" /> I wrote my code according to this blog post.

XML for Pager activity:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <android.support.v4.view.ViewPager
        android:id="@+id/instructionsViewPager"
        android:layout_width="match_parent"
        android:layout_height="match_parent" /> 
</LinearLayout>

Code for adapter:

public class MyPagerAdapter extends PagerAdapter {

    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return 2;
    }

    @Override
    public boolean isViewFromObject(View arg0, Object arg1) {
        return (arg0 == ((View) arg1));
    }

    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        ((ViewPager) container).removeView((View) object);
    }

    @Override
    public Object instantiateItem(ViewGroup container, int position) {
        LayoutInflater inflater = (LayoutInflater) container.getContext()
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        int resId = 0;
        switch (position) {
        case 1:
            resId = R.layout.instructions_page1;
            break;
        case 2:
            resId = R.layout.instructions_page2;
            break;
        }
        View view = inflater.inflate(resId, null);
        ((ViewPager) container).addView(view, 0);
        return view;
    }
}

Code for activity

public class Instructions extends Activity {

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.instructions);

        MyPagerAdapter adapter = new MyPagerAdapter();
        ViewPager pager = (ViewPager) findViewById(R.id.instructionsViewPager);
        pager.setAdapter(adapter);
        pager.setCurrentItem(0);
    }
}

for some reason, when I run this app, I get this following error list:

05-28 09:38:54.535: E/AndroidRuntime(18658): FATAL EXCEPTION: main
05-28 09:38:54.535: E/AndroidRuntime(18658): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.thepoosh/com.thepoosh.Instructions}: android.view.InflateException: Binary XML file line #7: Error inflating class android.support.v4.view.ViewPager
05-28 09:38:54.535: E/AndroidRuntime(18658):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1651)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1667)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at android.app.ActivityThread.access$1500(ActivityThread.java:117)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at android.os.Handler.dispatchMessage(Handler.java:99)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at android.os.Looper.loop(Looper.java:123)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at android.app.ActivityThread.main(ActivityThread.java:3691)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at java.lang.reflect.Method.invokeNative(Native Method)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at java.lang.reflect.Method.invoke(Method.java:507)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:847)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:605)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at dalvik.system.NativeStart.main(Native Method)
05-28 09:38:54.535: E/AndroidRuntime(18658): Caused by: android.view.InflateException: Binary XML file line #7: Error inflating class android.support.v4.view.ViewPager
05-28 09:38:54.535: E/AndroidRuntime(18658):    at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:581)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at android.view.LayoutInflater.rInflate(LayoutInflater.java:623)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at android.view.LayoutInflater.inflate(LayoutInflater.java:408)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at android.view.LayoutInflater.inflate(LayoutInflater.java:320)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at android.view.LayoutInflater.inflate(LayoutInflater.java:276)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:207)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at android.app.Activity.setContentView(Activity.java:1663)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at com.thepoosh.Instructions.onCreate(Instructions.java:11)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1615)
05-28 09:38:54.535: E/AndroidRuntime(18658):    ... 11 more
05-28 09:38:54.535: E/AndroidRuntime(18658): Caused by: java.lang.ClassNotFoundException: android.support.v4.view.ViewPager in loader dalvik.system.PathClassLoader[/data/app/com.thepoosh-1.apk]
05-28 09:38:54.535: E/AndroidRuntime(18658):    at dalvik.system.PathClassLoader.findClass(PathClassLoader.java:240)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at java.lang.ClassLoader.loadClass(ClassLoader.java:551)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at android.view.LayoutInflater.createView(LayoutInflater.java:471)
05-28 09:38:54.535: E/AndroidRuntime(18658):    at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:570)
05-28 09:38:54.535: E/AndroidRuntime(18658):    ... 20 more

so, I know it's failing because I'm using the android.support.v4.view.ViewPager, I tried playing with that and changing to plain ViewPager and importing android.support.v13 but it didn't help...

any thoughts on how to fix this?