I have TextBlock and Rectangle, both are sitting in an empty WPF4 window. Front Panel TextBlock and Rectangle Fill are set to SolidColorBrush with a value of # 80800000.
It looks like this:

The correct color is the rectangle (50% transparent burgundy), but TextBlock gives an even gray color. What's happening?
EDIT: Here's the XAML:
<Window x:Class="WpfApplication1.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="MainWindow" Height="350" Width="525"> <Grid> <TextBlock Foreground="#80800000" Height="100" HorizontalAlignment="Left" Margin="47,39,0,0" Text="TextBlock" VerticalAlignment="Top" Width="266" FontFamily="Arial" FontWeight="Bold" FontSize="56" /> <Rectangle Fill="#80800000" Height="100" HorizontalAlignment="Left" Margin="71,174,0,0" Stroke="{x:Null}" VerticalAlignment="Top" Width="200" /> </Grid> </Window>
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