<svg xmlns="http://www.w3.org/2000/svg">
  <script>//<![CDATA[

function add_watch()
{
  document.getElementById("e").x.baseVal.watch("0", function(){});
}

window.addEventListener("load", add_watch, false);

  //]]></script>

  <text id="e" x="10">foo</text>

</svg>