Reference to Listener Parent

I am having a weird problem with scope/reference. I am using a loop to preload a number of thumbs in one go, I am creating a different listener for each one on the fly and then passing event handlers for each one of them. This should not be difficult using a loop, but somehow I cannot access the the parent object on my listener and therefore I can’t do much with my thumbs after they are loaded.

Here is the relevant segment of my code. myThumb_mc is a temporary variable that does not exist when the loop finishes, you can copy and paste this code to test it though. It should work to that extent. (you’ll need an image1.jpg to be in the same directory)

var myThumb_mc = _root.createEmptyMovieClip("myThumb_mc", _root.getNextHighestDepth());

myThumb_mc.clipLoader = new MovieClipLoader();
myThumb_mc.clipLoader.loadClip("image1.jpg",myThumb_mc);

myThumb_mc.preloader = new Object();
myThumb_mc.clipLoader.addListener(myThumb_mc.preloader);

myThumb_mc.preloader.onLoadComplete = function() {
	trace(_parent);

	_parent.onRollOver = function() {
		this._alpha = 75;
};

The code above does not work because the reference _parent will not refer me to the _parent of my listener.

I managed to create a workaround by attaching a reference to my _parent object as a variable stored as a property of the listener.

var myThumb_mc = _root.createEmptyMovieClip("myThumb_mc", _root.getNextHighestDepth());

myThumb_mc.clipLoader = new MovieClipLoader();
myThumb_mc.clipLoader.loadClip("image1.jpg",myThumb_mc);

myThumb_mc.preloader = new Object();
myThumb_mc.clipLoader.addListener(myThumb_mc.preloader);

myThumb_mc.preloader.i = myThumb_mc;

myThumb_mc.preloader.onLoadComplete = function() {
	trace(this.i);

	this.i.onRollOver = function() {
		this._alpha = 75;
	};
	this.i.onRollOut = function() {
		this._alpha = 100;
	};
};

The code above works, but it does not look nice and it cannot be the right way of doing this.

Long question short, how can I access the parent of a listener from a listener object? ._parent does not work.