<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2008/11/27/auto-scrolling-a-textarea-control-in-flex/ -->
<mx:Application name="TextArea_maxVerticalScrollPosition_text"
        xmlns:mx="http://www.adobe.com/2006/mxml"
        layout="vertical"
        verticalAlign="middle"
        backgroundColor="white"
        creationComplete="init();"
        viewSourceURL="srcview/index.html">

    <mx:Script>
        <![CDATA[
            private var timer:Timer;

            private function init():void {
                timer = new Timer(500);
                timer.addEventListener(TimerEvent.TIMER, onTimer);
                timer.start();
            }

            private function onTimer(evt:TimerEvent):void {
                var now:String = new Date().toTimeString();
                var str:String = "[" + timer.currentCount + "] " + now;
                textArea.text += str + "\n";
                textArea.validateNow();
                textArea.verticalScrollPosition = textArea.maxVerticalScrollPosition;
            }
        ]]>
    </mx:Script>

    <mx:TextArea id="textArea"
            width="200"
            height="160" />

</mx:Application>