BeginForm() generates default.aspx? when on the Index view of the Home Controller

Question

On an MVC 1.0 site, Right out of the box, if I add an input type=submit button to a form created with Html.BeginForm i'll get an action of "/Default.aspx? This is not what I was expecting. This seems to be the case only with the sp-called default view.

The upshot of all this, that there will be a /defaul.aspx? in the addressbar when the user submits the form, which is obvioulsy undesirable in an MVC app.

I'm guessing I have to either name the route in the BeginForm, or change something in the Routing table. Coupl somebody confirm that assumption, and secondly, while I'm ok with either option, I would like to know why.

Here's some code to make things clearer: Add this to the Home/Index.aspx view

    <%using (Html.BeginForm())
  { %>
  <label for="input">Enter something here:</label>
                <%= Html.TextBox("input") %>
                <input type="submit" value="Submit" />
<%} %>

Add this to the HomeController.cs

[AcceptVerbs(HttpVerbs.Post)]
public ActionResult Index(string input)
{
    return View((object)Service.Text.Reverse(input)); // just a simple utility to flip the string order

}

Observe that when you press the submit buttion you'll get a default.aspx? (this is MVC 1.0)