RoleName always empty when adding role to CreateUserWizard

Hi,

first, sorry if this kind of problem ever asked and solved somewhere else, I couldn't found it.

I try to add role when registering a user.

But when I'm trying to add the user to the roles I always get an error message saying that the rolename is empty.

Here is my code, mostly taken from default register.aspx.

<asp:CreateUserWizard ID="RegisterUser" runat="server" EnableViewState="false"
        OnCreatedUser="RegisterUser_CreatedUser" DisplayCancelButton="True"
        LoginCreatedUser="False"><LayoutTemplate><asp:PlaceHolder ID="wizardStepPlaceholder" runat="server"></asp:PlaceHolder><asp:PlaceHolder ID="navigationPlaceholder" runat="server"></asp:PlaceHolder></LayoutTemplate><WizardSteps><asp:CreateUserWizardStep ID="RegisterUserWizardStep" runat="server"><ContentTemplate>
                      .....<p><asp:Label ID="UserRoleLabel" runat="server" AssociatedControlID="UserRole">Role:</asp:Label><asp:DropDownList ID="UserRole" runat="server" Width="320px"></asp:DropDownList><asp:RequiredFieldValidator ID="RoleRequired" runat="server" ControlToValidate="UserRole"
                                        CssClass="failureNotification" ErrorMessage="Role is required" ToolTip="Set the role to the user"
                                        ValidationGroup="RegisterUserValidationGrou">*</asp:RequiredFieldValidator></p>
                      .....</ContentTemplate><CustomNavigationTemplate></CustomNavigationTemplate></asp:CreateUserWizardStep></WizardSteps></asp:CreateUserWizard>

The code createduser event

        protected void RegisterUser_CreatedUser(object sender, EventArgs e)
        {
            string cUserName     = ((TextBox)RegisterUser.CreateUserStep.ContentTemplateContainer.FindControl("UserName")).Text;
            string cRole = ((DropDownList)RegisterUser.CreateUserStep.ContentTemplateContainer.FindControl("UserRole")).SelectedValue;

            Roles.AddUserToRole(cUserName, cRole);
        }

The problem is cRole is always empty, even I'm sure that the role in dropdown list has value.

Thanks in advance for the help.