[tex4ht] Error when using minted package

[Giuseppe Calà]

Hi, I just discovered tex4ebook and seems effectively an useful tool. I 
started experimenting with it after reading README file, so I'm a very newbie.

The problem I want to report is an error during epub creation when using 
"minted" package in tex file. minted requires '-shell-escape' option to call 
external program. My tex file compiles fine with latex, but I get 

! Package minted Error: You must invoke LaTeX with the -shell-escape flag.

when using tex4ebook, also with '-s' option, as stated in README.

Here it is a very minimal example:

\documentclass[a4paper,10pt]{article}
\usepackage[utf8]{inputenc}
\usepackage{minted}
\begin{document}

\begin{minted}{c++}
#include <iostream>
using namespace std;

int main()
{
   cout << "Hello Wordl!" << endl;
   return 0;
}
\end{minted}

\end{document}

You need Pygments from http://pygments.org/.

I'm using the following command:

tex4ebook -s sample.tex

Any idea how to solve this?

Very thanks.
Giuseppe