ListBox content not completely stretching across listbox - wpf

Question

I am trying to make a list box where I have complete control over the look of each item in the list box.
I can make the item horizontally stretch. However, there's this thin sliver of blue to the left of a selected item. (In the picture, the middle item is selected).
Can I make this blue strip go away?
alt text http://img44.imageshack.us/img44/949/boundlistboxdisplay.jpg
Here's the complete code.
<Window x:Class="SimpleListTemplate.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
>
<Window.Resources>
<XmlDataProvider x:Key="DcCharacters">
<x:XData>
<Characters xmlns="">
<Character HeroName="Catwoman" Identity="Selina Kyle" />
<Character HeroName="Batman" Identity="Bruce Wayne" />
<Character HeroName="Starman" Identity="Jack Knight" />
</Characters>
</x:XData>
</XmlDataProvider>
</Window.Resources>
<Grid>
<ListBox
ItemsSource="{Binding Source={StaticResource DcCharacters}, XPath=//Characters/*}"
HorizontalContentAlignment="Stretch">
<ListBox.ItemTemplate>
<DataTemplate>
<Label
Content="{Binding XPath=#HeroName}"
Height="40"
VerticalContentAlignment="Center"
Background="LightGreen"
BorderThickness="2"
BorderBrush="DarkGreen"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Grid>
</Window>

Answer 1

Here is an update for your code.
<Window x:Class="SimpleListTemplate.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<Window.Resources>
<XmlDataProvider x:Key="DcCharacters">
<x:XData>
<Characters xmlns="">
<Character HeroName="Catwoman" Identity="Selina Kyle" />
<Character HeroName="Batman" Identity="Bruce Wayne" />
<Character HeroName="Starman" Identity="Jack Knight" />
</Characters>
</x:XData>
</XmlDataProvider>
<Style TargetType="{x:Type ListBoxItem}" x:Key="ContainerStyle">
<Setter Property="Padding" Value="0,0,0,0"/>
</Style>
</Window.Resources>
<Grid>
<ListBox
ItemsSource="{Binding Source={StaticResource DcCharacters}, XPath=//Characters/*}"
ItemContainerStyle="{StaticResource ContainerStyle}"
HorizontalContentAlignment="Stretch">
<ListBox.ItemTemplate>
<DataTemplate>
<Label
Content="{Binding XPath=#HeroName}"
Height="40"
VerticalContentAlignment="Center"
Background="LightGreen"
BorderThickness="2"
BorderBrush="DarkGreen"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Grid>
</Window>
This may solve your problem.