I can sort when I use a standard DataGrid, but when I use a Telerik RadGridView, I can not sort. Why is that?
<sdk:DataGrid x:Name="rgvSearchResults" Grid.Row="1" AutoGenerateColumns="False" SelectionMode="Single"
SelectionChanged="rgvSearchResults_SelectionChanged_1" CanUserSortColumns="True">
<sdk:DataGrid.Columns>
<sdk:DataGridTextColumn Header="Division" Binding="{Binding Attributes[DIVISION]}" CanUserSort="True"></sdk:DataGridTextColumn>
<sdk:DataGridTextColumn Header="District" Binding="{Binding Attributes[DISTRICT]}" CanUserSort="True"></sdk:DataGridTextColumn>
<sdk:DataGridTextColumn Header="System" Binding="{Binding Attributes[SYS_NM]}" CanUserSort="True"></sdk:DataGridTextColumn>
<sdk:DataGridTextColumn Header="Sub-System" Binding="{Binding Attributes[SUBSYS_NM]}" CanUserSort="True"></sdk:DataGridTextColumn>
<sdk:DataGridTextColumn Header="Line" Binding="{Binding Attributes[LINE_NAME]}" CanUserSort="True"></sdk:DataGridTextColumn>
<sdk:DataGridTextColumn Header="Begin Series" Binding="{Binding Attributes[BEGIN_SERIES]}" CanUserSort="True"></sdk:DataGridTextColumn>
<sdk:DataGridTextColumn Header="Begin Station" Binding="{Binding Attributes[BEGIN_STATION]}" CanUserSort="True"></sdk:DataGridTextColumn>
<sdk:DataGridTextColumn Header="End Series" Binding="{Binding Attributes[END_SERIES]}" CanUserSort="True"></sdk:DataGridTextColumn>
<sdk:DataGridTextColumn Header="End Station" Binding="{Binding Attributes[END_STATION]}" CanUserSort="True"></sdk:DataGridTextColumn>
</sdk:DataGrid.Columns>
</sdk:DataGrid>
<telerik:RadGridView x:Name="rgvSearchResults" Grid.Row="1" AutoGenerateColumns="False" RowIndicatorVisibility="Collapsed"
SelectionChanged="rgvSearchResults_SelectionChanged" CanUserSortColumns="True" IsFilteringAllowed="True" IsReadOnly="True" ShowGroupPanel="False">
<telerik:RadGridView.Columns>
<telerik:GridViewDataColumn Header="Division" DataMemberBinding="{Binding Attributes[DIVISION]}"></telerik:GridViewDataColumn>
<telerik:GridViewDataColumn Header="District" DataMemberBinding="{Binding Attributes[DISTRICT]}"></telerik:GridViewDataColumn>
<telerik:GridViewDataColumn Header="System" DataMemberBinding="{Binding Attributes[SYS_NM]}"></telerik:GridViewDataColumn>
<telerik:GridViewDataColumn Header="Sub-System" DataMemberBinding="{Binding Attributes[SUBSYS_NM]}"></telerik:GridViewDataColumn>
<telerik:GridViewDataColumn Header="Line" DataMemberBinding="{Binding Attributes[LINE_NAME]}"></telerik:GridViewDataColumn>
<telerik:GridViewDataColumn Header="Begin Series" DataMemberBinding="{Binding Attributes[BEGIN_SERIES]}"></telerik:GridViewDataColumn>
<telerik:GridViewDataColumn Header="Begin Station" DataMemberBinding="{Binding Attributes[BEGIN_STATION]}"></telerik:GridViewDataColumn>
<telerik:GridViewDataColumn Header="End Series" DataMemberBinding="{Binding Attributes[END_SERIES]}"></telerik:GridViewDataColumn>
<telerik:GridViewDataColumn Header="End Station" DataMemberBinding="{Binding Attributes[END_STATION]}"></telerik:GridViewDataColumn>
</telerik:RadGridView.Columns>
</telerik:RadGridView>