[O] org --> odt with math

[Uwe Brauer]

Hi

Using org (git version) GNU emacs 26 on Ubuntu 14.04,
following
http://orgmode.org/manual/Working-with-LaTeX-math-snippets.html#fn-2
I have set
(setq org-latex-to-mathml-convert-command
                "/usr/bin/latexmlmath \"%i\" --presentationmathml=%o")

Latexmlmath is installed of course.

I try to convert the following file to odt with mathml
#+OPTIONS: LaTeX:t

This 
\begin{equation}
\label{eq:aned-ex:1}
\begin{cases}
  y^{\prime}&= -2000(y-\cos(t))\\
   y_0&=0 \qquad 0\leq t \leq 1.5
 \end{cases}
\end{equation}

But the equation is just exported as ASCII code. What do I miss?

Regards

Uwe Brauer