Commented Issue: ListPicker does not work with selecteditem bound [10796]

My case is simple, and my xaml snippet is

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<StackPanel>
<toolkit:ListPicker Margin="10,10,4,10" Header="birth place" SelectedIndex="{Binding Source={StaticResource settings}, Path=Birthplace, Mode=TwoWay}">
<sys:String>City 1</sys:String>
<sys:String>City 2</sys:String>
<sys:String>City 3</sys:String>
<sys:String>City 4</sys:String>
<sys:String>City 5</sys:String>
</toolkit:ListPicker>
</StackPanel>
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and appSettings class is similar to the class on MSDN.

http://msdn.microsoft.com/en-us/library/ff769510%28v=vs.92%29.aspx
Comments: ** Comment from web user: miao606 **

when settings.Birthplace not equals 0, the item actually not shown by default, it always shows the first item.