_alpha help actionscript 2

please help me with this

I want to reduce the alpha of a movie clip when mouse is rollOver the movie , the alpha will be continuously reducing over frames, i dont want to use tween.

import mx.transitions.Tween;
import mx.transitions.easing.*;

function turnOn() {
new Tween(bla_mc, “_alpha”, Regular.easeIn, 0, 60, .5, true);
}

function turnOff() {
new Tween(bla_mc, “_alpha”, Regular.easeIn, 60, 0, .3, true);
}

i this code when i rollOver the mouse on a movie clip, it shows the alpha reducing over time , and at roll out alpha increases over time. but if i rollOver and rollOut in fractions of seconds , it flickers (like 60-100 instead of from the current alpha lvl), So i am looking for some code that can help me in fixing this problem.

Lots of thanks in advance. :ponder: