Flash iPhone app pixelated once displayed on iPhone4

I have made the app in the larger resolution for iPhone4, and when I test it in 3GS it works/looks fine, the app scales DOWN accordingly. But when I test app on iPhone 4 it appears for reason to scale it down and then back up again creating a pix开发者_运维知识库elated look. This applies to vector assets and text within the flash project as well which is even weirder in my opinion. My SWF is 640x920px.

According to this post support for retina-display graphics is not yet supported. The two output sizes are either low-resolution iPhone or iPad. To wit:

The current version of PFI produces apps that run at 320x480 on iphones and ipods or 1024x768 on ipads. Support for 964x480 is something we're looking into adding for a future release.