[flexcoders] Is this normal behaviour for DataGrid ?

[Vaan S Lanko]

Hello Flexies, just curious is this normal behaviour or am I doing 
something stupendously wrong ?

I have recreated this issue in a small project with 2 files,

Service.as AS3 Class file

package
{
    public class Service
    {
        public function Service(_name:String,_price:Number,_category:String)
        {
            super();
            this.name = _name;
            this.price = _price;
            this.category = _category;
        }
           
        public var name:String;
        public var price:Number;
        public var category:String;
       }
}

and the main.mxml

<?xml version="1.0" encoding="utf-8"?>
<mx:WindowedApplication
    xmlns:mx="http://www.adobe.com/2006/mxml"; layout="vertical"
    initialize="initData()"
    >
   
    <mx:Script>
        <![CDATA[
            import mx.collections.ArrayCollection;
            private var dataArray:Array = new Array();
            private var testArrayCollection:ArrayCollection = new 
ArrayCollection();
           
            private function initData():void
            {
                dataArray.push(new Service("Blah 1",5.5,"Cat1"));
                dataArray.push(new Service("Blah 2",5.5,"Cat1"));
                dataArray.push(new Service("Blah 3",5.5,"Cat1"));
                dataArray.push(new Service("Blah 4",5.5,"Cat1"));
            }
           
            private function addToCollection():void
            {
                testArrayCollection.addItem(zomboCombo.selectedItem);
            }
           
        ]]>
    </mx:Script>
    <mx:DataGrid dataProvider="{testArrayCollection}">
        <mx:columns>
            <mx:DataGridColumn headerText="name" dataField="name"/>
            <mx:DataGridColumn headerText="price" dataField="price"/>
            <mx:DataGridColumn headerText="category" dataField="category"/>
        </mx:columns>
    </mx:DataGrid>
    <mx:ComboBox labelField="name" id="zomboCombo" 
dataProvider="{dataArray}"></mx:ComboBox>
    <mx:Button label="Add selected" click="addToCollection()"/>
   
</mx:WindowedApplication>

Run the app, select a Service with the combobox, hit the add 'selected 
button' a few times (consecutively without changing the combo selection) 
and with your mouse hover over the datagrid. Only the last entry will 
have a mouseover selection highlighted. I dont quite understand this 
behaviour, can someone enlighten me to what it is i'm doing wrong, or is 
it a bug ?

Cheers
Vaan