TabNavigator style

[sobaka11]

My application:

<mx:Style>
.a1{
backgroundImage: Embed("image.png");
} 
</mx:Style>

<mx:TabNavigator tabStyleName="a1">

<mx:VBox label="Accounts" width="300" height="150"
>
<!-- Accounts view goes here. -->
</mx:VBox>

<mx:VBox label="Stocks" width="300" height="150">
<!-- Stocks view goes here. -->
</mx:VBox>

<mx:VBox label="Futures" width="300" height="150">
<!-- Futures view goes here. -->
</mx:VBox> 

</mx:TabNavigator>

I want to put in my TabNavigator's tabs background image. Setting -backgroundImage: Embed("image.png");- in tab's style doesn't help. What should I change in my code?