<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" onload="runTest()">
<path id="thePath" d="M50 0 L 150 50" />
<pattern id="pat" patternUnits="userSpaceOnUse" x="0" y="0" width="400" height="400">
<text x="50" y="100">This text should be ABOVE the other line.</text>
<text>
<textPath id="theTP" xlink:href="#thePath">This text should be BELOW the other line.</textPath>
</text>
</pattern>
<rect width="400" height="400" fill="url(#pat)" stroke="black" stroke-width="1"/>
<script><![CDATA[
function runTest() {
var path = document.getElementById("thePath");
path.setAttribute("d", "M50 150 L 450 150");
}
]]></script>
</svg>