Image in Tooltip

Question

I have the following XAML code.
<Image Height="64" x:Name="image1" Stretch="Fill" ToolTipService.Placement="Top"
VerticalAlignment="Top" HorizontalAlignment="Left" Width="64"
Source="/Images/basket-full.png">
<Image.ToolTip>
<Border Width="128" Height="128">
<Image Source="{Binding Source, ElementName=image1, Mode=Default}"/>
</Border>
</Image.ToolTip>
</Image>
As you see above I want to display the same image in the tooltip, but it's not coming.
Can anybody help me?