Integrate a rollover effect into this code?

I have this code that i have modified a bit to work as a horizontal menu, but i need to add a rollover effect (a simple color change )to signify a link, but the code is complicated for me to integrate an effect, so i would like to place another rollover btn on top to get the effect, but of course this makes the button under obselete. Any suggestion on how i can get around this, i will paste the code below: Thanks for any suggestions


var anim_frames = 10; // Adjust speed
var opened = null;
var menus = [];
FindMenus = function(){
for (value in this){
if (this[value] instanceof MovieClip){
menus.push(this[value]);
}
}
menus.sort(SortByHorizontal);
}
SortByHorizontal = function(a, b){
return (a._x > b._x);
}
ApplyMenuMask = function(i){
var menu = menus*;
var mask = this.createEmptyMovieClip(“mask”+i, i);
mask._x = menu._x;
mask._y = menu._y;
mask.beginFill(0,100);
mask.moveTo(0, 0);
mask.lineTo(menu.title._width, 0);
mask.lineTo(menu.title._width, menu.title._height);
mask.lineTo(0, menu.title._height);
mask.endFill();
menu.setMask(mask);
menu.masker = mask;
}
StartMenuPosition = function(i){
var menu = menus*;
if (i == 0){
menu._x = menu.masker._x = 0;
}else{
var menu_above = menus[i-1];
menu._x = menu.masker._x = Math.round(menu_above._x + menu_above.title._width);
}
}
MenuOpen = function(){
var menu = this;
menu.masker._width += (1+menu._width-menu.title._width)/anim_frames;
if (menu.masker._width >= menu._width){
menu.masker._width = menu._width;
delete this.onEnterFrame;
}
PositionMenusBelow(menu.i);
}
MenuClose = function(){
var menu = this;
menu.masker._width -= (1+menu._width-menu.title._width)/anim_frames;
if (menu.masker._width <= menu.title._width){
menu.masker._width = menu.title._width;
delete this.onEnterFrame;
}
PositionMenusBelow(menu.i);
}
TitleButtonPress = function(){
var menu = this._parent;
if (opened){
if (opened == menu){
menu.onEnterFrame = MenuClose;
opened = null;
}else{
opened.onEnterFrame = MenuClose;
menu.onEnterFrame = MenuOpen;
opened = menu;
}
}else{
menu.onEnterFrame = MenuOpen;
opened = menu;
}
}
PositionMenusBelow = function(i){
var menu = menus*;
if (i < menus.length-1){
var menu_below = menus[i+1];
for (i=i+1; i<menus.length; i++){
if (menus* == menu_below){
menus*._x = menus*.masker._x = menu._x + menu.masker._width;
}else{
var menu_above = menus[i-1];
menus*._x = menus*.masker._x = menu_above._x + menu_above.masker._width;
}
}
}
}
Init = function(){
FindMenus();
for (var i=0; i<menus.length; i++){
menus*.i = i;
ApplyMenuMask(i);
StartMenuPosition(i);
menus*.title.onPress = TitleButtonPress;
}
}
Init();