SVG generation has a XML mistake on tag <tspan>

[Reynaldo A ROSAS]

The open tag of tspan is set as if it was a closing tag:
<g transform="translate(25.34,117.91)" visibility="hidden" gadfly:scale="50.0">
<g class="primitive">
<text text-anchor="end" dy="-0em" transform="rotate(-90,0, 0)">10</tspan>-3.75</tspan></text>
</g>
</g>
``