How to use DatePicker on Overlay?

How to use DatePicker on Overlay?

Hi,
 I have an overlay as a modal pop up. There is a gridview on it and one of the field is textbox which should be a datepicker. But the problem is datepicker does not show up on overlay. How can I do this?

Best Regards.

Thanks in advance.

Here is the sample code:

var triggers = $(".modalInput1").overlay({
            // some mask tweaks suitable for modal dialogs
            mask: { color: '#a1eaee',
                loadSpeed: 150,
                opacity: 0.8
            },
            closeOnClick: false
        });

<div class="modal1" id="prompt1">
        <div class="close">
        </div>
        <h2>
            Manuel Delivery</h2>
        <asp:UpdatePanel ID="UpdatePanel4" runat="server" UpdateMode="Conditional">
            <ContentTemplate>
                <asp:GridView ID="GridView4" runat="server" AutoGenerateColumns="false" DataSourceID="SqlDataSource5"
                    AllowPaging="True" AllowSorting="True" PageSize="1" OnRowCreated="GridView3_RowCreated"
                    DataKeyNames="ItemId" EmptyDataText="<center><img src='Images/NoData.jpg' border='0'></center>">
                    <RowStyle CssClass="normalrowstyle" />
                    <AlternatingRowStyle CssClass="alternatingrowstyle" />
                    <Columns>
                        <asp:BoundField DataField="RequestID" HeaderText="RequestID" SortExpression="RequestID"
                            ItemStyle-Width="150px" />
                        <asp:BoundField DataField="VendorID" HeaderText="VendorID" SortExpression="VendorID"
                            ItemStyle-Width="150px" />
                        <asp:BoundField DataField="VendorNo" HeaderText="VendorNo" SortExpression="VendorNo"
                            ItemStyle-Width="150px" />
                        <asp:BoundField DataField="Quantity" HeaderText="Quantity" SortExpression="Quantity"
                            ItemStyle-Width="150px" />
                        <asp:BoundField DataField="ItemName" HeaderText="Item Name" SortExpression="ItemName"
                            ItemStyle-Width="150px" />
                        <asp:BoundField DataField="DeliveryId" HeaderText="DeliveryId" SortExpression="DeliveryId"
                            ItemStyle-Width="150px" />
                        <asp:BoundField DataField="PackageId" HeaderText="PackId" SortExpression="PackId"
                            ItemStyle-Width="150px" />
                        <asp:BoundField DataField="FirstName" HeaderText="First Name" ReadOnly="True" SortExpression="FirstName"
                            ItemStyle-Width="200px" />
                        <asp:BoundField DataField="LastName" HeaderText="Last Name" SortExpression="LastName"
                            ItemStyle-Width="150px" />
                        <asp:BoundField DataField="City" HeaderText="City" SortExpression="City" ItemStyle-Width="100px" />
                        <asp:BoundField DataField="District" HeaderText="District" SortExpression="District"
                            ItemStyle-Width="100px" />
                        <asp:BoundField DataField="ItemId" HeaderText="ItemId" SortExpression="ItemId" ItemStyle-Width="150px"
                            Visible="false" />
                        <asp:TemplateField HeaderText="Delivery Date" SortExpression="DeliveryDate" ItemStyle-Width="150px">
                            <ItemTemplate>
                                <asp:TextBox ID="myDate" runat="server" />
                            </ItemTemplate>
                        </asp:TemplateField>
                    </Columns>
                    <PagerTemplate>
                        &nbsp; Page
                        <asp:TextBox ID="txtGoToPage" runat="server" AutoPostBack="true" OnTextChanged="GoToPageGrdV4_TextChanged"
                            CssClass="gotopage" />
                        of
                        <asp:Label ID="lblTotalNumberOfPages" runat="server" />
                        &nbsp;
                        <asp:Button ID="Button3" runat="server" CommandName="Page" ToolTip="Previous Page"
                            CommandArgument="Prev" CssClass="previous" />
                        <asp:Button ID="Button4" runat="server" CommandName="Page" ToolTip="Next Page" CommandArgument="Next"
                            CssClass="next" />
                    </PagerTemplate>
                    <HeaderStyle CssClass="headerstyle" />
                    <PagerStyle CssClass="pagerstyle" />
                </asp:GridView>
                <asp:Button ID="Button2" runat="server" Text="Send" />
            </ContentTemplate>
        </asp:UpdatePanel>
        </div>






































































<script>
        $(document).ready(function () {
            $("#myDate").datepicker();

        });

    </script>