silverlight的DataGrid中添加DatePicker控件使用滚动条滚动数据有误

silverlight的DataGrid中添加DatePicker控件,初始设定DatePicker中的时间,连续使用滚动条滚动,初始设定DatePicker的值会随机改变.

   <sdk:DataGrid Grid.Row="1" HorizontalAlignment="Stretch" Name="dataGrid1" VerticalAlignment="Stretch" >
        <sdk:DataGrid.Columns>
            <sdk:DataGridTemplateColumn CanUserResize="False">
                <sdk:DataGridTemplateColumn.CellTemplate>
                    <DataTemplate>
                        <Grid>
                               <sdk:DatePicker SelectedDate="{Binding Path=Time}"></sdk:DatePicker>
                        </Grid>
                    </DataTemplate>
                </sdk:DataGridTemplateColumn.CellTemplate>
            </sdk:DataGridTemplateColumn>
        </sdk:DataGrid.Columns>
    </sdk:DataGrid>