I'm following [this](http://www.dansoltesz.com/post/2011/07/29/silverlight-listbox-autoscroll-behavior.aspx) example for an auto-scrolling behavior on a ListBox on WP7 Mango RC targeting 7.1.

In my Xaml:

```
 <ListBox x:Name="StatusMessages"
                 Height="100"
                 ItemsSource="{Binding StatusMessages, Mode=TwoWay}"
                 DisplayMemberPath="Message"
                 Grid.Row="3">
            <i:Interaction.Behaviors>
                <behaviors:ListBoxItemAutoScrollBehavior FoundItem="{Binding FoundItem}" />
            </i:Interaction.Behaviors>
        </ListBox>

```

The behavior:

```
 public class ListBoxItemAutoScrollBehavior : Behavior<ListBox>
    {       
        public object FoundItem
        {
            get { return GetValue(FoundItemProperty); }
            set { SetValue(FoundItemProperty, value); }
        }

        public static readonly DependencyProperty FoundItemProperty = DependencyProperty.Register("FoundItem", typeof (object), typeof (ListBoxItemAutoScrollBehavior), new PropertyMetadata(FoundItemChanged));

        private static void FoundItemChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            ((ListBoxItemAutoScrollBehavior) d).AssociatedObject.ScrollIntoView(e.NewValue);
        }
    }

```

I have a breakpoint set at the FoundItemChanged method and would expect to see it hit when I set FoundItem in my ViewModel and fire NotifyProperyChanged. Only, it doesn't work, any ideas why or what I might be doing wrong?

Thanks.

**update**: breakpoints are hit for OnAttached and OnDetaching in the behavior.

**update** 2: This works in a regular Silveright 4 application.

**update** 3: Using version 3.8.5.0 of System.Windows.Interactivity fixed it.