Reflecting on executing assembly

I have the following linq statement

builtIn = (from type in Assembly.GetExecutingAssembly().GetTypes()
where type.IsClass && type.Namespace.ToUpper().StartsWith("PD3.MODULES.BUILTIN.")
let onStartMethod = type.GetMethod("Init")
where onStartMethod != null
select onStartMethod
);

but it only works if I leave out the

&& type.Namespace.ToUpper().StartsWith("PD3.MODULES.BUILTIN") part :(

Further down the code, I have to take this into account using

if (builtInInit.ToString开发者_开发百科() == "Pd3.Module Init()")

but I really don't like this solution so here's my 2 part question

1. Is there a better way of getting methods where the namespace condition is correct? and
2. Why do the type.Namespace fail?

With Regard, Stig

---

Types in the root namespace can have a null namespace, so it is calling .StartsWith on a null; just eliminate those first:

... && type.Namespace != null && type.Namespace. {blah}