how to Grid without horizantal scroll and give vertical scroll header style

Question

Hi all i use radgrid with scrolling but when scrolling is on the header (see the link for more info) of grid above the scroll looks different than the content header and on IE8 horizantal scroll is shown

The html markup of radgrid is below

        <telerik:RadGrid HeaderStyle-Height="20px"  HeaderStyle-Width="500" BackColor="#ebebeb" ID="PropertySelectGrid" AutoGenerateColumns="false"
            runat="server" GridLines="None" Width="450px"  OnItemCreated="PropertySelectGrid_ItemCreated" TableLayout="Fixed" >
            <MasterTableView CommandItemDisplay="None"  BackColor="#ebebeb" Width="425px" CurrentResetPageIndexAction="SetPageIndexToFirst"
                Dir="LTR" Frame="Border" TableLayout="Fixed">                   
                <Columns>                        
                    <telerik:GridBoundColumn ItemStyle-Width="0px" DataField="Id" Visible="false" DataType="system.string"
                        ReadOnly="True" SortExpression="Id" UniqueName="Id">
                    </telerik:GridBoundColumn>
                    <telerik:GridTemplateColumn ItemStyle-HorizontalAlign="Justify" ItemStyle-Width="20px" HeaderStyle-Width="20px" UniqueName="Selection">
                        <ItemTemplate>
                            <asp:CheckBox Width="15px" ID="SelectCheckBox" runat="server" TextAlign="Left"  AutoPostBack="false" />
                        </ItemTemplate>
                    </telerik:GridTemplateColumn>
                    <telerik:GridBoundColumn DataField="Name" ItemStyle-Width="150px" HeaderStyle-Width="150px" DataType="system.string"
                        HeaderText="Adı" ReadOnly="True" SortExpression="Name" UniqueName="Name">
                    </telerik:GridBoundColumn>
                    <telerik:GridTemplateColumn UniqueName="PropertyValueColumn" ItemStyle-Width="200" HeaderStyle-Width="234" HeaderText="Değeri">
                        <ItemTemplate>
                        </ItemTemplate>
                    </telerik:GridTemplateColumn>
                </Columns>
                <NoRecordsTemplate>
                    Listelenecek Kayıt Bulunmamaktadır.</NoRecordsTemplate>
            </MasterTableView>
            <ClientSettings>
                <Scrolling AllowScroll="True" UseStaticHeaders="True" SaveScrollPosition="True" FrozenColumnsCount="1">
                </Scrolling>
            </ClientSettings>
        </telerik:RadGrid>

so how to disable horizantal scroll and headerstyle for vertical scroll like the content header? Thanks