Email validation on createuserwizard

Hi

I  am using the createuserwizard but i want to check if the email is valid. Currently if i put any text in the email field it accepts it. I am using the template my code is below cant see anything wrong with it?

      <asp:Label ID="EmailLabel" runat="server" AssociatedControlID="Email" ForeColor="Black">E-mail:</asp:Label>
                                    </td>
                                    <td>
                 &n ...