[NTG-context] MathML in ConTeXt conforming to MathML3?

Does the MathML in ConText conforms to the MathML3 specification? (see http://www.w3.org/TR/MathML3/chapter5.html) I find that with \usemodule[mathml] (1) <semantics><annotation encoding="application/x-tex">TeX-code</annotation></semantics> does not typesets, but (2) <semantics><annotation encoding="tex">TeX-code</annotation></semantics> does. As I understand from the specification, (1) should have been correct, but does not processes the TeX and the attribute "application/x-tex" seems not to be recognized. Does ConTeXt-MathML deviates in this respect from the current standard? Or do I miss some important fact? Hans van der Meer