PagerTabStrip ignoring android:textcolor attribute

Question

I currently have a PagerTabStrip widget (from rev 21 of the support library) defined like this:

<android.support.v4.view.PagerTabStrip
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:layout_gravity="top"
      android:paddingBottom="10dp"
      android:paddingTop="10dp"
      android:textAppearance="@style/Theme.TTBase.PagerTabStripText"/>

With the textappearance style defined like this:

<style name="Theme.TTBase.PagerTabStripText">
    <item name="android:textStyle">italic</item>
    <item name="android:textSize">16sp</item>>
    <item name="android:textColor">#7A378B</item>
</style>

The issue I'm currently experiencing is that the android:textSize and android:textStyle attributes of the style are applied to the PagerTabStrip as expected, but for some reason the android:textColor is being ignored and the text in the pagerTabStrip is black (the default color).

What could be causing the textColor to be ignored, and is there a fix available for this issue?