Is it possible to change a MC's anchor/registration point with AS?

programming flash
1

Wondering if it is possible to change a MC’s anchor/registration point with AS. So when I use the following a mc grows from different points.


movieclip.prototype.grow = function(pClip, xValue, yValue, speed)
{
	pClip.onEnterFrame = function()
	{
		trace("ease this "+this._width)
		this._xscale += (xValue-this._width)/speed;
		this._yscale += (yValue-this._height)/speed;
		if (this._width == xValue && this._height == yValue)
		{
		delete this.onEnterFrame;
		}
			
	}
}