Actually, they are styles and not properties (which may explain the errors), but also I'd suggest making sure you have a recent Flex 4 SDK, and not the one that shipped with Flash Builder 4 beta1. I'm not sure if those APIs were in the beta1 SDK.
You can see an example of these styles in action at http://blog.flexexamples.com/2009/06/04/setting-left-and-right-margins-on-a-spark-textarea -control-in-flex-4/.
yeah that was the problem.
shoot im getting compile errors now. do you have instructions on updating flash builder 4 sdk? I may have done something wrong.
But it depends on what compiler errors you're seeing. Also, if you're updating from the Flash Builder 4 beta SDK (18.104.22.16819, I belive) to a new nightly build, you'll undoubtedly run into a few of our API renames. For a fairly comprehensive list, see http://opensource.adobe.com/wiki/display/flexsdk/Rename+List.
If neither of those solve the issue, let me know and we can take a look at getting your app back on track.