Trouble extending line element

Hi there,
I'm currently trying to extend the SVG DTD to allow me to have a new
element in the <line> element like this:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE svg PUBLIC '-//W3C//DTD SVG 1.1//EN'
"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd" [
<!ENTITY % SVG.line.extra.content "| hit">
<!ELEMENT hit (queryId, queryString) >
<!ELEMENT queryId (#PCDATA)>
<!ELEMENT queryString (#PCDATA)> ]>
<svg xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xmlns:xalan="http://xml.apache.org/xalan"
     xmlns:xlink="http://www.w3.org/1999/xlink"
     xmlns="http://www.w3.org/2000/svg"
     style="fill-opacity:1; color-rendering:auto;
color-interpolation:auto; stroke:black; text-rendering:auto;
stroke-linecap:square; stroke-miterlimit:10; stroke-opacity:1;
shape-rendering:auto; fill:black; stroke-dasharray:none;
font-weight:normal; stroke-width:1; font-family:'Dialog';
font-style:normal; stroke-linejoin:miter; font-size:12;
stroke-dashoffset:0; image-rendering:auto;"
     xsi:schemaLocation="http://www.w3.org/1999/xlink "
     width="200"
     height="100">
    <text x="5" y="15" style="font-size:10; font-family:serif;
stroke:none;" xml:space="preserve">Test matrix</text>
    <rect x="0" y="30" width="10000" height="70" fill="black"
stroke="black" stroke-width="1"/>
    <g stroke="white">
        <line y2="50" style="fill:none;" x1="100" x2="400" y1="50">
            <hit>
                <queryId>123123131232132</queryId>
                <queryString>AAAATGACGAGAGAGAGAGAGAGAG"></queryString>
            </hit>
        </line>
    </g>
</svg>
 
but it's failing to accept the XML as a valid SVG when using Batik's
Java JSVGCanvas object. However, Mozilla firefox can view the image
fine.

Can someone let me know what I'm doing wrong?
 
Many thanks,
 
Ben

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