build flex viewer3.0 source code to .swc file

lilu1

i get flex viewer2.5 source code, create a flex Library project named "xyz" in flashBuilder4.6,
copy the flex viewer3.0 source code files to the project "xyz", and add swc file refrence to "agslib-2.5-2011-11-30.swc',
then building is ok, generate a file "xyz.swc".
     create a flex Application project named "MyApp", it  add project refrence to "xyz",  building is ok,  but throw a exception while runing the "MyApp", the exception information is "null refrence ".  excepiton locate Flex viewer2.5 source file "MapManager.mxml" . why "styleManager.getStyleDeclaration("com.esri.ags.components.supportClasses.InfoWindow")" return value is null????

     protected override function partAdded(partName:String, instance:Object):void
            {
                super.partAdded(partName, instance);
                if (instance === map)    
                {
                    var cssStyleDeclaration:CSSStyleDeclaration = styleManager.getStyleDeclaration("com.esri.ags.components.supportClasses.InfoWindow")
                    cssStyleDeclaration.setStyle("backgroundColor", getStyle('contentBackgroundColor'));
                    styleManager.setStyleDeclaration("com.esri.ags.components.supportClasses.InfoWindow", cssStyleDeclaration, true);
                }
            }

lilu1

set the agslib-2.5-2011-11-30.swc into External-Library-Path , is ok. but throw a new exception

ReferenceError: Error #1065: Variable "com.esri.ags::FeatureSet" undefine�??
 at _Main_FlexInit$/init()
 at mx.managers::SystemManager/http://www.adobe.com/2006/flex/mx/internal::kickOff()
 at mx.managers::SystemManager/http://www.adobe.com/2006/flex/mx/internal::preloader_completeHandler()
 at flash.events::EventDispatcher/dispatchEventFunction()
 at flash.events::EventDispatcher/dispatchEvent()
 at mx.preloaders::Preloader/timerHandler()
 at flash.utils::Timer/_timerDispatch()
 at flash.utils::Timer/tick()

additional remarks, run this code, throw exception [ATTACH=CONFIG]14475[/ATTACH]

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