Text Alignment not working, did I do something wrong?

Here's the deal, I have a TextField that I want to align centered. it is a dynamic TextField, so I want to use AutoSize.

The problem is, I've tried TextFieldAutoSize and TextFormatAlign. Nothing works. The text is still aligned at left (the size expands to the right)

The whole code:

var usernameStringFormat:TextFormat = new TextFormat();

usernameStringFormat.align = TextFormatAlign.CENTER;

usernameStringFormat.font = "Space Age";

usernameStringFormat.size = 28;

usernameStringFormat.color = 0xff6000;

var username:TextField = new TextField();

username.defaultTextFormat = usernameStringFormat;

//username.autoSize = TextFieldAutoSize.CENTER;

username.text = "LOREM IPSUM";

//username.setTextFormat(usernameStringFormat);

I've tried these combos:

Only TextFormatAlign

Only TextField AutoSize

Both Align and AutoSize

all three of them implemented with these combos:

Only defaultTextFormat

Only setTextFormat

Both defaultTextFormat and setTextFormat

Nothing works. I'm going nuts here.

EDIT:

Okay, I got past this nutcase. I simply used username.x - = username.width/2; subsequent additions to the text property causes the textfield to expand properly to the left and right. Is this the way it is intended?