Load images and onRollOver button play mask and reveal image?

1

I have this loadImages function


var pics:Array = ["image0.jpg","image1.jpg","image2.jpg","image3.jpg"];
var imagePath = "imgs/";
function loadImages(){
	for(i=0;i<pics.length;i++){
			var pic:MovieClip = this.createEmptyMovieClip("pic"+i,i,{_width:740,_height:230,_y:157,_x:(60*i)});
			pic.id = i;
			pic._x = (60)*(i);//just to check if all 4 images are loaded
			pic.loadMovie(imagePath + pics*);
		}
}
loadImages();
//now for the onrollover/mask
function imageMask(pic){

	pic.setMask(theMask);
	theMask.play();
}

function buildNav() {
	for(i=0;i<navArray.length;i++){
		this["navBtn"+i].navTxt.text = navArray*;
		this["navBtn"+i].onRollOver = function(){
			imageMask("pic"+i);//play the mask and reveal corresponding image
			}
		}
}

Any suggestions or tutorials???