GridSplitter in a Frame; expand beyond border problems

I've got a generic view for displaying data in a Silverlight RIA application. Basically, the view takes in a parameter which is the query required by RIA to get the data, and the data is displayed using autogenerated fields.

Here's part of the XAML code for the view.

        <Grid Grid.Column="0">
            <Grid.RowDefinitions>
                <RowDefinition x:Name="DataGridRow"/>
                <RowDefinition Height="Auto"/>
                <RowDefinition x:Name="DataFormRow"/>
                <RowDefinition Height="Auto" x:Name="EditRow"/>
            </Grid.RowDefinitions>
            <ria:DomainDataSource Name="SQLDomainDataContext" LoadingData="SQLDomainDataContext_LoadingData" LoadSize="45" SubmittedChanges="SQLDomainDataContext_SubmittedChanges" SubmittingChanges="SQLDomainDataContext_SubmittingChanges" LoadedData="SQLDomainDataContext_LoadedData">
                <ria:DomainDataSource.SortDescriptors>
                    <ria:SortDescriptor Direction="Descending" PropertyPath="BaseProperties.CreatedOn" />
                </ria:DomainDataSource.SortDescriptors>
            </ria:DomainDataSource>
            <Grid>
                <Grid.RowDefinitions>
                    <RowDefinition />
                    <RowDefinition Height="Auto"/>
                </Grid.RowDefinitions>
                <sdk:DataGrid  Grid.Row="0" AutoGenerateColumns="True" Name="dataGrid" ItemsSource="{Binding}" DataContext="{Binding Path=Data, Mode=TwoWay}" IsReadOnly="True" AutoGeneratingColumn="dataGrid_AutoGeneratingColumn" SelectionChanged="dataGrid_SelectionChanged" />
                <custCont:LocalizedDataPager Grid.Row="1" x:Name="pager" Source="{Binding Path=Data}" PageSize="15" DisplayMode="FirstLastPreviousNext" />
            </Grid>

            <Border Grid.Row="1">
                <Border.Background>
                    <LinearGradientBrush EndPoint="1,0.5" StartPoint="0,0.5">
                        <GradientStop Color="#FF9D9D9D" Offset="0" />
                        <GradientStop Color="#FFDBDBDB" Offset="1" />
                    </LinearGradientBrush>
                </Border.Background>
                <StackPanel Orientation="Horizontal" HorizontalAlignment="Center">
                    <Ellipse Fill="Black" HorizontalAlignment="Center" Width="4" Height="4" Margin="8,0"/>
                    <Ellipse Fill="Black" HorizontalAlignment="Center" Width="4" Height="4" Margin="8,0"/>
                    <Ellipse Fill="Black" HorizontalAlignment="Center" Width="4" Height="4" Margin="8,0"/>
                </StackPanel>
            </Border>
            <sdk:GridSplitter Grid.Row="1" HorizontalAlignment="Stretch" Background="Transparent" Opacity="0"/>

            <data:DataForm Grid.Row="2" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Name="DF" AutoCommit="False" 
                           DataContext="{Binding Path=Data, Mode=TwoWay}" ItemsSource="{Binding}" 
                           AutoGeneratingField="DF_AutoGeneratingField" EditEnded="DF_EditEnded" DeletingItem="DF_DeletingItem" Style="{StaticResource DataFormStyle}"/>

            <Grid Grid.Row="3">
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="Auto"/>
                    <ColumnDefinition />
                    <ColumnDefinition Width="Auto"/>
                    <ColumnDefinition Width="Auto"/>
                    <ColumnDefinition Width="Auto"/>
                </Grid.ColumnDefinitions>
                <Button Grid.Column="0" Name="btnHideDF" Content="{Binding Source={StaticResource ApplicationResources}, Path=ApplicationStrings.ShowEntities_HideDfBtn}" MinWidth="10" Margin="2" Click="btnHideDF_Click" />
                <Button Grid.Column="2" Name="bRefresh" Content="{Binding Source={StaticResource ApplicationResources}, Path=ApplicationStrings.ShowEntities_RefreshBtn}" MinWidth="75" Margin="2" Click="bRefresh_Click" IsEnabled="{Binding Path=CanLoad}" />
                <Button Grid.Column="3" Name="btnCacnelChanges" Content="{Binding Source={StaticResource ApplicationResources}, Path=ApplicationStrings.ShowEntities_CancelChangesBtn}" Margin="2" IsEnabled="{Binding Path=HasChanges}" Click="btnCacnelChange开发者_StackOverflow社区s_Click" Visibility="Collapsed" />
                <Button Grid.Column="4" Name="bSubmit" Content="{Binding Source={StaticResource ApplicationResources}, Path=ApplicationStrings.ShowEntities_SubmitBtn}" MinWidth="75" Margin="2" IsEnabled="{Binding Path=HasChanges}" Click="bSubmit_Click" />
            </Grid>
        </Grid>

When the view is displayed in a singular Frame, all is well. But when it is displayed on a page with TWO frames, odd things begin to happen. If the user grabs the splitter and moves it all the way to the top, beyond the frames boundaries, the DataForm will expand endlessly. This isn't a big issue, but it looks ugly, and makes the buttons at the bottom vanish from sight.

What's going on here? Why is this happening? How can I prevent this behaviour?

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Apparently my Google-fu was weak.

I found this today, and it describes the exact same problem I had, as well as a possible solution.

Still, I didn't expect this to be a bug in SL...