MouseEvent funktioniert nicht mit Maske

[hothead89]

Hallo
ich habe folgenden Code:

<?xml version="1.0" encoding="utf-8"?>
<s:Group xmlns:fx="http://ns.adobe.com/mxml/2009" 
		 xmlns:s="library://ns.adobe.com/flex/spark" 
		 xmlns:mx="library://ns.adobe.com/flex/mx" 
		 addedToStage="init()"
		 width="470" height="200"
		 
		 mouseDown="startSlidingTicker(event)"
		 >
	<fx:Declarations>
		<s:ColorMatrixFilter id="filterBlackAndWhite" matrix="{m_matrixBlackAndWhite}"/>
	</fx:Declarations>
	
	<fx:Script>
		<![CDATA[
			import mx.controls.Image;
private var m_arrayNewsSliderInactive:Array = new Array();
			private var m_arrayNewsSliderActive:Array = new Array();
			
			//Setup SliderContent
			private function init() : void
			{
				var i:int;
				for ( i = 0; i < 10; i++ )
				{
					var tempPic:Image = new Image();
					tempPic.source = "gfx/ticker/mac_ticker_test_01.png";
					tempPic.filters = new Array ( filterBlackAndWhite );
					tempPic.addEventListener( MouseEvent.MOUSE_OVER, undoBlackAndWhiteFilter, false, 0, true );
					tempPic.addEventListener( MouseEvent.MOUSE_OUT, doBlackAndWhiteFilter, false, 0, true );
					tickerSlider.addElement( tempPic );
					
					m_arrayNewsSliderInactive.push();
				}
				
				
			}

// HOVER EFFECT
			
			private var redLum:Number = 0.2225;
			private var greenLum:Number = 0.7169;
			private var blueLum:Number = 0.0606;
			
			[Bindable]
			private var m_matrixBlackAndWhite:Array = 
				[redLum, greenLum, blueLum, 0, 0,
				redLum, greenLum, blueLum, 0, 0,
				redLum, greenLum, blueLum, 0, 0,
				0, 0, 0, 1, 0];
			
			private function undoBlackAndWhiteFilter ( event:MouseEvent ) : void
			{
				event.currentTarget.filters = null;
			}
			
			private function doBlackAndWhiteFilter ( event:MouseEvent ) : void
			{
				event.currentTarget.filters = new Array(filterBlackAndWhite);
			}
		]]>
	</fx:Script>


	<s:Group width="100%" height="100%" maskType="alpha">

		<s:mask>
			<s:Group width="470" height="200">
				<s:Rect width="100%" height="100%">
					<s:fill>
						<s:LinearGradient>
							<s:entries>
								<s:GradientEntry color="0x000000" alpha="0" ratio="0"/>
								<s:GradientEntry color="0x000000" alpha="1" ratio=".3" />
								<s:GradientEntry color="0x000000" alpha="1" ratio=".7"/>
								<s:GradientEntry color="0x000000" alpha="0" ratio="1"/>
							</s:entries>
						</s:LinearGradient>
					</s:fill>
				</s:Rect>
			</s:Group>
		</s:mask>
		
		<s:Group id="tickerSlider" width="100%" height="100%" >
			<s:layout>
				<s:HorizontalLayout horizontalAlign="left" verticalAlign="top" gap="10"/>
			</s:layout>
			
		</s:Group>
	
	</s:Group>
	
	
</s:Group>

wenn ich allerdings in der Gruppen nun die Maske drinne habe funktioniert der Eventlistener für den MouseOver und MouseOut nicht. warum nicht?!? wenn ich die maske rausnehme funktioniert es tadellos!

Vielen Dank für die Hilfe!
Gruß