Hello David and thanks for your response,
Please correct me but this article seems not to be related to my question unless the solution is to download the latest SDK
Its about what happened when the latest sdk was downloaded at that time, flashbuilder release is now aligned with the later sdk's, code generated with flashbuilder beta has things like incorrect name spaces.
xmlns:mx="library://ns.adobe.com/flex/halo" in beta2
xmlns:mx="library://ns.adobe.com/flex/mx" in release, thats why you had name space errors.
By making changes to your beta code as per the thread(and the link provided to one of the Adobe staffs blogs your code should then work with the Flashbuilder release.
Thanks again for the help David. I'll try to make some time to revise that blog post for the release.
Jason San Jose
Software Engineer, Flash Builder