<svg xmlns="http://www.w3.org/2000/svg" width="400" height="200">
<script><![CDATA[
function zoom(evt)
{svgdoc=evt.target.ownerDocument;obj=svgdoc.getElementById("objet");
obj.setAttribute("transform","matrix(2 0 0 2 100 75)")}
function normal(evt)
{svgdoc=evt.target.ownerDocument;obj=svgdoc.getElementById("objet");
obj.setAttribute("transform","matrix(1 0 0 1 100 75)")}
]]></script>
<g id="objet" transform="matrix(1 0 0 1 100 75)" onmouseover="zoom(evt)" onmouseout="normal(evt)">
<rect x="-50" y="-25" width="100" height="50" style="fill:yellow" />
<text x="0" y="0" text-anchor="middle" font-size="12" font-family="Arial" fill="black">A little zoom</text>
</g>
</svg>