As some of you asked me recently
to show how I used the PureMVC Loadup utility in a Flash project, I made a new demo : http://www.tekool.net/blog/2009/12/06/using-puremvc-loadup-utility-with-flash-ide/
The demo contains four new classes needed to compile a project from the Flash IDE or from a Flash Builder pure ActionScript project. It's all what the Loadup utility need to work from Flash without using the Flex SDK. Thanks to Philip Sexton for that.
I suppose that a minor update to the Loadup Utility could officially add this classes by separating flex and flash packages. But there are many other ways to achieve this.
Hope this helps.