Project Advice - Flex

I am trying to create a chat application in Flex but I need some advice on several things. Here is the interface:

http://www.redshiftltd.co.uk/dev/flexchat/

I need to know how I would go about coding this to function properly. The white box on the right is a List, this is where usernames will appear. The big box is where messages will appear and the small on where messages will be inputted. Would a MySql databse + PHP be a good combination to use for user authtencation and message storage. Have I used the correct elements and code for my project? Any other critisisms and advice are gladly welcomed.

Cheers

Alex


Source Code:


<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute">
<mx:Panel width="700" height="415" layout="absolute" verticalCenter="-0" horizontalCenter="0" title="Chat" id="chatWindow">
<mx:TextArea x="10" y="10" width="514" height="282"/>
<mx:TextInput x="10" y="300" width="425"/>
<mx:Button x="443" y="300" label="Send" width="81" id="submit"/>
<mx:List x="532" y="10" width="138" height="282"></mx:List>
<mx:Label x="10" y="347" text="Chat - 2008" alpha="1.0"/>
</mx:Panel>


</mx:Application>

your link is not working just to let you know.

thanks for that, i just reorganised my projects!