MSTEST PrincipalPermission

How do you unit test code decorated with the PrincipalPermission attribute?

For example, this works:

class Program
{
    static void Main(string[] args)
    {
        AppDomain.CurrentDomain.SetPrincipalPolicy(PrincipalPolicy.WindowsPrincipal);
        var c = new MyClass();
    }
}

[PrincipalPermission(SecurityAction.Demand, Role = @"BUILTIN\Users")]
class MyClass
{
    public MyClass()
    {
        Console.WriteLine("This works.");
    }
}

This throws a SecurityException:

[TestClass]
public class UnitTest1
{
    [TestInitialize]
    public void TestInitialize()
    {
        AppDomain.CurrentDomain.SetPrincipalPolicy(PrincipalPolicy.WindowsPrincipal);
    }

    [TestMethod]
    public void TestMethod1() 
    { 
        var c = new MyClass();
    }
}

Any ideas?