Is RecreateDatabaseIfModelChanges available in WPF?

I'm trying out Entity Framework Code First. I can't seem to find the assembly/namespace to use for RecreateDatabaseIfModelChanges in WPF 4.0. Is this an ASP.NET-only feature? If not, what assembly should I reference?

Here's my code:

using System;
using System.Data.Entity;
using System.Windows;
using CodeFirstTester.Models;

namespace CodeFirstTester
{
    public partial class App : Application
    {
        static App()
        {
            // this fails:
            Database.SetInitializer(new RecreateDatabaseIfModelChanges<NerdDinners>());

            // The type or namespace name 'RecreateDatabaseIfModelChanges'
            // could not be found (are you missing a using directive or
            // an assembly reference?)                

            using (var nerdDinners = new NerdDinners())
            {
                var dinner = new Dinner()
                {
                    Title = "Party at Scott's House",
                    EventDate = DateTime.Parse("12/31/2010"),
                    Address = "Building 40",
                    HostedBy = "scottgu@microsoft.com"
                };
                nerdDinners.Dinners.Add(dinner);
                nerdDinners.SaveChanges();
            }
        }
    }
}