O Spinner não pode carregar uma matriz inteira?

Eu tenho um aplicativo, que tem um Spinner que eu quero preencher com alguns números (4,8,12,16). Criei um objeto de matriz inteira em strings.xml com os itens mencionados acima, defino as entradas do Spinner como matriz inteira e, quando executo o aplicativo, obtenho:

04-19 23:38:48.016: ERROR/AndroidRuntime(10193): java.lang.NullPointerException
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:355)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.widget.ArrayAdapter.getView(ArrayAdapter.java:323)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.widget.AbsSpinner.onMeasure(AbsSpinner.java:198)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.view.View.measure(View.java:7965)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:2989)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:888)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.widget.LinearLayout.measureVertical(LinearLayout.java:350)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.widget.LinearLayout.onMeasure(LinearLayout.java:278)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.view.View.measure(View.java:7965)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:2989)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.widget.FrameLayout.onMeasure(FrameLayout.java:245)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.view.View.measure(View.java:7965)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.widget.LinearLayout.measureVertical(LinearLayout.java:464)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.widget.LinearLayout.onMeasure(LinearLayout.java:278)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.view.View.measure(View.java:7965)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:2989)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.widget.FrameLayout.onMeasure(FrameLayout.java:245)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.view.View.measure(View.java:7965)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.view.ViewRoot.performTraversals(ViewRoot.java:763)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.view.ViewRoot.handleMessage(ViewRoot.java:1632)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.os.Handler.dispatchMessage(Handler.java:99)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.os.Looper.loop(Looper.java:123)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at android.app.ActivityThread.main(ActivityThread.java:4310)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at java.lang.reflect.Method.invokeNative(Native Method)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at java.lang.reflect.Method.invoke(Method.java:521)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
04-19 23:38:48.016: ERROR/AndroidRuntime(10193):     at dalvik.system.NativeStart.main(Native Method)

Assim que eu mudei o array para um string-array, isso funciona bem. Isso é normal? Sei que posso (e vou) apenas converter os valores da matriz de strings para um int, mas parece estranho que eu precise.

Obrigado!

EDIT: Alguém? Qualquer coisa?