Created Unassigned: AvalonDock Now Loses Alt Key Adornments [20882]

I've been using AvalonDock (2.0) for some time now, being key for managing documents in an IDE. In the last several months, I've noticed that Alt key adornments are no longer showing up for controls within AvalonDock, though the Alt key commands are executing as expected. See the image below where the Alt key adornments are showing up in the menu, but not for the buttons inside AvalonDock:


What is particularly interesting about this issue, that it appears to be triggered by an environmental setting or condition.

As demonstrated in this [video](http://www.youtube.com/watch?v=D-S_PGJoTkc) (at 2:07), the alt key adornments are working for a control within AvalonDock. But, if I now use the very same executable I used in that video, the alt key adornments do not work.

I also built a very simple test application which loads a couple of documents of type Item, where Item is a simple class with a Name property:

<Window x:Class="WpfApplication1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:WpfApplication1"
xmlns:avalonDock="clr-namespace:Xceed.Wpf.AvalonDock;assembly=Xceed.Wpf.AvalonDock"
xmlns:avalonDockLayout="clr-namespace:Xceed.Wpf.AvalonDock.Layout;assembly=Xceed.Wpf.AvalonDock"
xmlns:avalonDockControls="clr-namespace:Xceed.Wpf.AvalonDock.Controls;assembly=Xceed.Wpf.AvalonDock"
Title="MainWindow" Height="500" Width="500">
<Window.Resources>
<ResourceDictionary>
<DataTemplate DataType="{x:Type local:Item}">
<StackPanel Orientation="Vertical">
<Label Content="Item:" />
<TextBox Text="{Binding Name}"/>
<Button Content="_ClickMe" />
</StackPanel>
</DataTemplate>
</ResourceDictionary>
</Window.Resources>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="*"></RowDefinition>
<RowDefinition Height="Auto"></RowDefinition>
</Grid.RowDefinitions>
<avalonDock:DockingManager Grid.Row="0" DocumentsSource="{Binding}">
<avalonDockLayout:LayoutRoot>
<avalonDockLayout:LayoutPanel Orientation="Horizontal">
<avalonDockLayout:LayoutDocumentPane/>
</avalonDockLayout:LayoutPanel>
</avalonDockLayout:LayoutRoot>
</avalonDock:DockingManager>
<Button Grid.Row="1" Content="_Test" />
</Grid>
</Window>

Even with this simple application, the Alt key adornments show up for the Test button outside of AvalonDock, but not for the ClickMe buttons for the controls within AvalonDock. I've also done this with the sample application here, so this seems for sure to be a bug.

Any ideas on how to correct or workaround this issue?