枚举解析似乎不适用于Fluent NHibernate

public class EnumTypeConverter<T> : IUserType
{
    public object NullSafeGet(IDataReader rs, string[] names, object owner)
    {
        var value = NHibernateUtil.String.NullSafeGet(rs, names[0]);
        if (value == null)
            return null;

        return Enum.Parse(typeof(T), (string)value);
    }

    public void NullSafeSet(IDbCommand cmd, object value, int index)
    {
        if (value == null)
        {
            ((IDataParameter)cmd.Parameters[index]).Value = DBNull.Value;
        }
        else
        {
            ((IDataParameter)cmd.Parameters[index]).Value = value.ToString();
        }
    }

    public object DeepCopy(object value)
    {
        return value;
    }

    public object Replace(object original, object target, object owner)
    {
        return original;
    }

    public object Assemble(object cached, object owner)
    {
        return cached;
    }

    public object Disassemble(object value)
    {
        return value;
    }

    public SqlType[] SqlTypes
    {
        get { return new[] { NHibernateUtil.String.SqlType }; }
    }

    public Type ReturnedType
    {
        get { return typeof(T); }
    }

    public bool IsMutable
    {
        get { return false; }
    }

    public new bool Equals(object x, object y)
    {
        if (ReferenceEquals(x, y))
            return true;

        if (x == null || y == null)
            return false;

        return x.Equals(y);
    }

    public int GetHashCode(object x)
    {
        return x.GetHashCode();
    }
}

public class MyEntityMap : ClassMap<MyEntity>
{
    public MyEntityMap()
    {
        Map(x => x.MyEnumProperty)
            .CustomType<EnumTypeConverter<MyEnum>>();
    }
}