private boolean attrsContainInkscape(Attributes atts) {
        int length = atts.getLength();
        for (int i = 0; i < length; i++) {
            String uri = atts.getURI(i);
            if ("http://www.inkscape.org/namespaces/inkscape" == uri
                    || "http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd" == uri) {
                return true;
            }
        }
        return false;
    }
@see nu.validator.checker.Checker#startElement(java.lang.String,
     java.lang.String, java.lang.String, org.xml.sax.Attributes)
src/nu/validator/checker/UncheckedSubtreeWarner.java