this produces a problem
but works in mono:
../../testcase2.cs:24: circularity detected in class definition
------
namespace System
{
[Serializable]
public class Object
{}

[Serializable]
public abstract class Attribute
{ }

[Serializable]
public sealed class GooAttribute
: Attribute
{

}

[Goo] // ../../testcase2.cs:24: circularity detected in class definition

public sealed class SerializableAttribute
: Attribute
{
}
}