DESPERATE! Problems with reenabling a button (For AS guru)

Hey Guys! Im a newbie on ActionScript language, and im gonna to explain an issue that i have with ActionScript.

Scenario:

Button “boton1” is pressed
Movie “quienes” is loaded. (MC “quienes” works like a pop-up"
Button “boton1” is disabled.

boton1 CODE:

on (release) {
 this.attachMovie("quienes", "window", 0);
 window._x = 624;
 window._y = 348;
 boton1.enabled=false
}

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“boton1” must be disabled because when “quienes” is loaded, it keeps on workingin a rollover action.
Button “boton2” is pressed
Movie “quienes” is unloaded.

boton2 CODE:

on (press){
this.removeMovieClip("window");
}

How can Button “boton1” become enabled again?

Thanks Everybody!