Flex :: Simple TextField - Using SWFObject To Embed Flash

I'm using swfobject to embed my flash. I've created a simple textfield using FlexBuilder. It's an AS3 project, which extends Sprite. I've set its width to be 640 and height to 450. Then, in the swfobject parameters of the page, I've also set 640 x 450. I've made the background nice and red and ugly so you can see it. [URL]. It seems to be the right dimensions.

But I've got a textfield which is supposed to be almost the same size and height. This runs fine in FlexBuilder (is the right size) but is all messed up once I add swfobject Can anyone see what is happening? I just looked at it and it looks ok. But then I refreshed the page and the textfield is postage-stamp size (again -- this is the original behavior I saw.) It's now looking OK in firefox but not in IE8. Flash is supposed to look the same in all browsers?

AS3 code:
package {
import flash.display.Sprite;
import flash.text.TextField;
import flash.text.TextFormat;
import flash.text.Font;
[Code] .....