Extending Membership Wizard - Insert command fails

Hi Folks,

I'm trying to implement a modified membership wizard using asp.net.  The application works without the extended membership control and it appears that everything is present and correct when debugging but when I uncomment the ThisDataSource.Insert() command it throws an error saying the provider isn't present!

Any thoughts?

Here is the code that is failing:
[code]
    Protected Sub CreateUserWizard1_CreatedUser(ByVal sender As Object, ByVal e As System.EventArgs) Handles CreateUserWizard1.CreatedUser
        Dim UserNameTextBox As New TextBox
        Dim ThisDataSource As SqlDataSource
        Dim user As MembershipUser
        Dim UserGuid As New Object

        UserNameTextBox = CreateUserWizardStep1.ContentTemplateContainer.FindControl("Username")
        ThisDataSource = DirectCast(CreateUserWizardStep1.ContentTemplateContainer.FindControl("InsertExtraInfo"), SqlDataSource)

        user = Membership.GetUser(UserNameTextBox.Text)
        UserGuid = user.ProviderUserKey

        Response.Write("User = " & user.ToString() & "<BR>")
        Response.Write("User Guid = " & UserGuid.ToString() & "<BR>")
        Response.Write("This Data Source = " & ThisDataSource.ProviderName.ToString() & "<BR>")

        ThisDataSource.InsertParameters.Add("User_Id", UserGuid.ToString())
        Response.Write(ThisDataSource.InsertCommand & "<BR>")
        '        Response.Write(ThisDataSource..ToString() & "<BR>")

        Dim aParameter As Parameter
        For Each aParameter In ThisDataSource.InsertParameters
            Response.Write(aParameter.Name & "<BR>")
        Next

        ThisDataSource.Insert()

    End Sub
[/code]

Here is the datasource within the page
[code]
                    <asp:sqlDataSource ID="InsertExtraInfo" runat="server" ConnectionString="<%$ConnectionStrings:Test_Authorisation_DB %>"
                    InsertCommand="INSERT INTO [T_UserAgencies] (ua_UserId, ua_AgencyId, ua_StartDate) Values (@User_Id, @Agency_Id, @StartDate)"
                    ProviderName = "<%$ ConnectionStrings:Test_Authorisation_DB %>">
                    <InsertParameters>
                    <asp:ControlParameter Name="Agency_Id" Type="String" ControlId="Agency" PropertyName="Text" />
                    <asp:ControlParameter Name="StartDate" Type = "DateTime" ControlId="StartDate_TextBox" PropertyName="Text" />
                 
                    </InsertParameters>
                </asp:sqlDataSource>
[/code]

and here is the output (where the insert is commented out)
[code]
User = dfgdg
User Guid = ba3b032d-0c2a-4cc5-8828-a27e443d5418
This Data Source = Data Source=TCBC17985;Initial Catalog=Test_Authentication_DB;Integrated Security=True
INSERT INTO [T_UserAgencies] (ua_UserId, ua_AgencyId, ua_StartDate) Values (@User_Id, @Agency_Id, @StartDate)
Agency_Id
StartDate
User_Id
[/code]

So everything appears to be present, it just falls on its backside.  

Any help gratefully received.

Thanks