textbox under datalist itemtemplate not dynamically populating

Hi All,

I have a multiline textbox which has formatting toolbar loaded from javascript code on page_load.The requirement is to populate the textbox with a default value once a dropdownlist(which is out of datalist) has particular selected item.

I am trying to bind the datalist with the default text in Postback.

    .aspx
<asp:DataList RepeatDirection="Vertical" ID="DataListExeSummary" runat="server"  OnItemDataBound="DataListExeSummary_Databound" OnEditCommand="Edit_Command" >
                                <ItemTemplate>
                                    <table  runat="server" width="100%" id="TableExec">
                                        <tr>
                                            <td>
                                                <asp:UpdatePanel ID="UpdatepanelExe" runat="server">
                                                    <ContentTemplate>
                                                        <asp:Label ID="DataListLabelExeSummary" Text='<%# BIND("FIELD_NAME" ) %>' runat="server"
                                                            SkinID="txt_LabelProjectScreen"></asp:Label>
                                                        <asp:Label ID="DataListLabelExeSummaryReq" Text="*" runat="server" Visible="false"
                                                            SkinID="MandatoryTextRed"></asp:Label>
                                                    </ContentTemplate>
                                                    <Triggers>
                                                        <asp:AsyncPostBackTrigger ControlID="ddlProjectStatus" EventName="SelectedIndexChanged" />
                                                        <%--Added by Kverma for Q3 Enhancement--%>
                                                        <%--<asp:AsyncPostBackTrigger ControlID="ddlSubType" EventName="SelectedIndexChanged" />----%>
                                                    </Triggers>
                                                </asp:UpdatePanel>
                                            </td>
                                        </tr>
                                        <tr>
                                            <td>
                                                <%--<asp:UpdatePanel ID="UpdatePanelProjectExpense" runat="server">
                                                    <ContentTemplate>--%>                                                        
                                                      <asp:TextBox id="textExecutiveSummary" TextMode="multiline" runat="server" Text= '<%# BIND("FIELD_VALUE" )%>'/>
                                                       
                                                        <asp:HiddenField ID="HiddenFieldManageControlsId" Value='<%# BIND("MANAGE_CONTROLS_ID" ) %>'
                                                            runat="server" /> 
                                                        <asp:HiddenField ID="HiddenFieldKey" Value='<%# BIND("FIELD_KEY" ) %>' runat="server" />
                                                        <asp:RequiredFieldValidator ID="rfvCustomEditorExecutiveSummary" runat="server" ControlToValidate="textExecutiveSummary"
                                                            ValidationGroup="ValidatePage" Display="None" ErrorMessage="Validate"></asp:RequiredFieldValidator>                                                       
                                                            
                                                          <asp:LinkButton ID="EditLinkButton" runat="server" Text="Edit" CommandName="Edit" Visible="false"></asp:LinkButton>                                                            
                                                            
                                                    <%--</ContentTemplate>
                                                    
                                                    <Triggers>
                                                        <asp:AsyncPostBackTrigger ControlID="ddlSubType" EventName="SelectedIndexChanged" />
                                                    </Triggers>
                                                </asp:UpdatePanel> --%>      
.cs page

protected void Page_Load(object sender, EventArgs e)
    {
        try
        {
                    if (!IsPostBack)
                    {
                        LoadExecutiveSummaryTable();//To load datalist
                                               }
                    }
                    else
                    {
                        if (Request.Form["__EVENTTARGET"] == ddlSubType.UniqueID)
                        {
                        string selected = ddlSubType.SelectedItem.Text.ToString();
                        if (selected == "Licensing")
                        {
                            if (ddlSubType.SelectedItem.Text == "Licensing")
                            {
                                DataListExeSummary.DataSource = null;
                                DataListExeSummary.DataBind();
                                DataSet dsExec = (DataSet)Session[UIConstants.EXECUTIVESUMMARY];
                                for (int i = 0; i < dsExec.Tables[0].Rows.Count; i++)
                                {
                                    dsExec.Tables[0].Rows[i]["FIELD_VALUE"] = "<P  style= \"MARGIN: 0in 0in 0pt\">See Report</P>";
                                }
                                dsExec.AcceptChanges();
                                Session[UIConstants.EXECUTIVESUMMARY] = dsExec;
                                DataListExeSummary.DataSource = dsExec;
                                DataListExeSummary.DataBind();

                            }
                          }

                        }
                }
        }
        catch (Exception ex)
        {
            if (ExceptionManager.HandleException(ex, CommonConstants.POLICY_NAME))
            {
                UIHelper.RedirectToErrorPage();
                throw ex;
            }
        }
    }


If I uncomment the UpdatePanel stuuf in aspx the textbox is being populated with default text but the toolbar is not being bount to textbox.it populated as normal textbox.

Thanks
Pallavi