how methodinfo threadcontext class?

i'm perplexing this:

type threadcontexttype = typeof(application).getnestedtype("threadcontext", system.reflection.bindingflags.nonpublic);
methodinfo fdoidlemi = threadcontexttype.getmethod("fdoidle", bindingflags.nonpublic |
    bindingflags.instance, null, new type[] { typeof(int32) }, null);

threadcontexttype ok nonetheless fdoidlemi null. i know there something wrong getmethod since fdoidle comes unsafenativemethods.imsocomponent interface.

how that? thanks.