[Platform_iOS]Spark TextArea bugged for iOS

Problem Description: Hi,

every time I catch spark TextArea focus, the text is slightly cut. After repeated event focusOut and focusIn for TextArea, the text disappears completely.
<s:View xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark" title="TestTextArea">
<fx:Declarations>
<!-- Place non-visual elements (e.g., services, value objects) here -->
</fx:Declarations>

<s:TextArea width="300"
x="393" y="664"
editable="true"
borderVisible="false"
contentBackgroundColor="0xFFFFFF"
contentBackgroundAlpha="0"
skinClass="spark.skins.mobile.TextAreaSkin"
text="Lorem ipsum dolor sit amet, consectetur adipisicing elit."/>
<s:TextArea width="300"
x="393" y="964"
editable="true"
borderVisible="false"
contentBackgroundColor="0xFFFFFF"
contentBackgroundAlpha="0"
skinClass="spark.skins.mobile.TextAreaSkin"
text="Lorem ipsum dolor sit amet, consectetur adipisicing elit."/>
</s:View>

Steps to Reproduce:
Flash builder -> New mobile project -> create two spark TextArea components -> often change focus

Actual Result:
disappearing text

Expected Result:
no disappearing text

My video: http://www.youtube.com/watch?feature=player_embedded&v=xDJSaf-V2DQ