Simple Sorting not working properly

[Michaël Kiekens]

I have a simple grid where I allow sorting. the datasource is filled with the needdatasource event. This funtion puts an IEnumerable<Canidate> into the datasource.
When I click the header of a column for the first time, everything works wel. When I click the header of the column next to the previous column, the column to right of the column I clicked is then sorted. also the sortmode is not changing when click multiple times on the same header. I have also tested this with auto generate columns, but this produces the same error.

Does anyone has an idea what is going on?

here is my code behind:

  protected void CandidateListGrid_NeedDataSource(object source, GridNeedDataSourceEventArgs e)
        {
            RadComboBox lastNameInput = (RadComboBox)FilterData.FindControl("LastNameInput");
            RadComboBox firstNameInput = (RadComboBox)FilterData.FindControl("FirstNameInput");
            RadDatePicker dateLastContractFromInput = (RadDatePicker)FilterData.FindControl("DateLastContractFromInput");
            RadDatePicker dateLastContractUntilInput = (RadDatePicker)FilterData.FindControl("DateLastContractUntilInput");
            RadComboBox StatusComboBox = (RadComboBox)FilterData.FindControl("StatusComboBox");

            var statusItems = from itm in StatusComboBox.Items
                              where ((CheckBox)itm.FindControl("CheckBox")).Checked
                              select itm.Value;

            CandidateListGrid.DataSource = this.presenter.ListCandidates(
                ((lastNameInput != null) ? lastNameInput.Text : "")
                , ((firstNameInput != null) ? firstNameInput.Text : "")
                , statusItems
                , ((dateLastContractFromInput != null) ? dateLastContractFromInput.SelectedDate : DateTime.MinValue)
                , ((dateLastContractUntilInput != null) ? dateLastContractUntilInput.SelectedDate : DateTime.MinValue)
                );

        }

here is my ascx

 <telerik:RadGrid ID="CandidateListGrid" runat="server" AllowPaging="True" AllowSorting="true" GridLines="None"
        AutoGenerateColumns="False" PageSize="10"
        AllowMultiRowSelection="True" EnableEmbeddedSkins="False" Skin="USGFOEXTelerik"
        OnNeedDataSource="CandidateListGrid_NeedDataSource" >
        <MasterTableView ClientDataKeyNames="ID">
            <Columns>
                <telerik:GridBoundColumn DataField="LastName" HeaderText="Naam" SortExpression="LastName"
                    UniqueName="LastName">
                </telerik:GridBoundColumn>
                <telerik:GridBoundColumn DataField="FirstName" HeaderText="Voornaam" SortExpression="FirstName"
                    UniqueName="FirstName">
                </telerik:GridBoundColumn>
                <telerik:GridBoundColumn DataField="ContractState" HeaderText="Status" SortExpression="ContractState"
                    UniqueName="ContractState">
                </telerik:GridBoundColumn>
                <telerik:GridBoundColumn DataField="LastContractDate" DataType="System.DateTime"
                    HeaderText="Laatste contract" SortExpression="LastContractDate" UniqueName="LastContractDate">
                </telerik:GridBoundColumn>
            </Columns>
        </MasterTableView>
    </telerik:RadGrid>

here is my Candidate class:

  public class Candidate
    {
        public int Id { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public DateTime LastContractDate { get; set; }
        public string ContractState { get; set; }
}

[Rosen]

Hello Michaël,

I'm afraid that I'm unable to recreate the behavior you have described using the provided information. I have attached a sample test page, please take a look maybe I'm missing something obvious.

Greetings,
Rosen
the Telerik team

[Michaël Kiekens]

your sample application is indeed working. I will try to digg a little deeper to find what combination of controls is causing this.
Thanks for your help already