function appendCanvas() {
	var cc = document.getElementById('comment_content')
	if (cc) {
		svgobj = document.createElement('object');
		svgobj.setAttribute('data','http://www.rikkertkoppes.com/tests/svg/drawingcanvas.svg');
		svgobj.setAttribute('type','image/svg+xml');
		svgobj.setAttribute('height','144');
		svgobj.setAttribute('width','650');
		svgobj.setAttribute('class','drawingcanvas');
		svgobj.setAttribute('id','comment_drawing');
		
		svgdt = document.createElement('dt');
		svgdt.appendChild(document.createTextNode('drawing (optional)'));
		
		svgdd = document.createElement('dd');
		svgdd.appendChild(svgobj);
		
		svgconf = document.createElement('dd');
		chk = svgconf.appendChild(document.createElement('input'));
		chk.setAttribute('name','comment_embed_drawing');
		chk.setAttribute('id','comment_embed_drawing');
		chk.setAttribute('type','checkbox');		
		chklbl = svgconf.appendChild(document.createElement('label'));
		chklbl.setAttribute('for','comment_embed_drawing');
		chklbl.appendChild(document.createTextNode('embed drawing'));
		
		cc.parentNode.parentNode.appendChild(svgdt);
		cc.parentNode.parentNode.appendChild(svgdd);
		cc.parentNode.parentNode.appendChild(svgconf);
		
		frm = cc.form;
		frm.addEventListener('submit',submitSVG,false);
		
	}
}

function getSVGXML() {
	var serializer = new XMLSerializer();
	return serializer.serializeToString(document.getElementById('comment_drawing').contentDocument.getElementById('canvas'));
}

function submitSVG(e) {
	var cc = document.getElementById('comment_content');
	if (cc.form.elements['comment_embed_drawing'].checked) {
		cc.value += String.fromCharCode(1)+getSVGXML();
	}
}