markup-size not working with Label-path

[GralfR]

Hi! I didn't find anything inside the templates-manual if this is not possible, not supported or just not working: the markup-size has no effect on a Label-path; there is just no markup visible. I broke it down to a simple template, which could be done better with a Label-rectangle, but it's just for clarifying, that it's not working with a path. But markup-size is more important on paths, because creating a markup-margin inside a path may be as complicated as the path itself. Markup-size could make it so easy if it was working... This is my test-template:

  <Template brand="-Test-" part="Markup1" size="A4" description="just to test markup-size">
    <Label-path id="0"  x_waste="0mm" y_waste="0mm" d_units="mm"
      d="M 0 0
        L 100 0 L 100 100 L 0 100
        Z" >
      <Markup-margin size="10mm"/>
      <Layout nx="1" ny="1" x0="45mm" y0="18mm" dx="150mm" dy="140mm"/>
    </Label-path>
  </Template>

Thanks