normalizedPathSegList

Hi,
Do you know if the normalizedPathSegList attribute of path elements
will soon be implemented in firefox ?
I try to write a function to update points of a path from a
transformation matrix. It's all ok except for elliptical arcs :
I can't find the correct coefficients for r1 r2 and angle.
Is it simplier to approximate arcs with bezier curves, like the
normalizedPathSegList would do ?
I wrote an example at http://jsfiddle.net/s32LX/, but I join the code
below anyway.
Best regards,
Yannick Bochatay
http://ybochatay.fr




SVGPathElement.prototype.mtx2attrs = function(mtx) {

  var seg,letter,point,pt={},
  angle = Math.atan2(mtx.b, mtx.a),
  svg = this.ownerSVGElement,
  list = this.pathSegList,
  i=0, N = list.numberOfItems;

 /* this.rel2abs();  function that change relative paths to absolute
*/

  for (;i<N;i++) {
       seg = list.getItem(i);
       letter = seg.pathSegTypeAsLetter;

        ['','1','2'].forEach(function(ind) {

            if (seg['x'+ind] === undefined && seg['y'+ind] ===
undefined) { return; }

            if (seg['x'+ind] !== undefined) { pt['x'+ind] =
seg['x'+ind]; }
            if (seg['y'+ind] !== undefined) { pt['y'+ind] =
seg['y'+ind]; }


            var point = svg.createSVGPoint();
            point.x = pt['x'+ind]; point.y = pt['y'+ind];
            point = point.matrixTransform(mtx);

            seg['x'+ind] = point.x;
            seg['y'+ind] = point.y;
         });

       if (angle!==0 && (letter === 'H' || letter === 'V')) {
 
this.pathSegList.replaceItem( this.createSVGPathSegLinetoAbs(seg.x,seg.y) ,
i );
       }
       else if (letter === 'A') {
           /*what to do in that case ??
           seg.r1 = ?
           seg.r2 = ?
           seg.angle+= angle ?
           */
       }
    }
};