AS2 Fade Effect Movie Clipille

on (rollOver) {
_root.alphaMinus = 1;
}
on (rollOut) {
_root.alphaMinus = 0;
}
onClipEvent (enterFrame) {
if (_root.alphaMinus == 1) {
if (_alpha>40) {
this._alpha -= 10;
}
} else {
if (_alpha<100) {
this._alpha += 10;
}
}
}