Help scaling a MC with easing

Hi guys,

I’m trying to get a MC to resize & ease on rollover using actionscript rather than tweening.

I’ve got the following code on the MC:

on (rollOver) {
this._xscale = 120;
this._yscale = 120;
}

on (rollOut){
this._xscale = 100;
this._yscale = 100;
}

which scales the MC on rollover but I want to add easing to make it smoother.

Any suggestions?
Cheers.