as3 thingy problem

import flash.events.Event;

stage.addEventListener(MouseEvent.MOUSE_DOWN,gotomouse)

function gotomouse(event:Event){
ball.x = mouseX; // are you sure you don't want to animate this?
ball.y = mouseY;  //  "  "
var gravity:Number = 1
trace(gravity);

if(!ball.hasEventListener(Event.ENTER_FRAME)){

ball.addEventListener(Event.ENTER_FRAME,fall);

}
}

function fall(event:Event){
gravity += gravity/2;

ball.y += gravity;

if(ball.y>stage.stageHeight+ball.height){

ball.removeEventListener(Event.ENTER_FRAME,fall);

ball.parent.removeChild(ball);

}
}

*********************************************************************************************************************

/*  the above will work for one ball, but that's going to be pretty boring, so i would expect something different like clicking on one of a number of balls will trigger its fall */

for(var i=0;i<ballNum;i++){

this["ball_"+i].addEventListener(MouseEvent.MOUSE_DOWN,gotomouse);

}

function gotomouse(e:Event){
e.currentTarget.x = mouseX
e.currentTarget.y = mouseY
e.currentTarget.gravity = 1;

if(!e.currentTarget.hasEventListener(Event.ENTER_FRAME)){

e.currentTarget.addEventListener(Event.ENTER_FRAME,fall);

}
}

function fall(e:Event){
e.currentTarget.gravity += e.currentTarget.gravity/2;

e.currentTarget.y += e.currentTarget.gravity;

if(e.currentTarget.y>stage.stageHeight+ball.height){

e.currentTarget.removeEventListener(Event.ENTER_FRAME,fall);

e.currentTarget.removeEventListener(MouseEvent.MOUSE_DOWN,gotomouse);

e.currentTarget.parent.removeChild(e.currentTarget);

}
}