ASP.NET MVC RC2 - Why can't I use the normal validation options? e.g. RequiredFieldValidator

Question

I'm trying to validate a basic form, can i not use the standard validation controls? Everywhere i'm looking seems to try and use something like the below

<%= Html.ValidationSummary() %>

<% using (Html.BeginForm()) {%>

    <fieldset class="fields">
        <legend>Create New Contact</legend>
        <p>
            <label for="task">Task Name:</label>
            <%= Html.TextBox("task") %>
            <%= Html.ValidationMessage("task", "*") %>
        </p>
        <p class="submit">
            <input type="submit" value="Create" />
        </p>
    </fieldset>

<% } %>

I thought id be able to use the standard components? Any pointers would be brilliant!