找不到语言环境“ en_US”的已编译资源包“消息”。 从4.0迁移到4.6

Question

When migrate flex SDK from 4.0 to 4.6. I meet such an error in runtime.

 Error: Could not find compiled resource bundle 'messaging' for locale 'en_US'.
 at mx.resources::ResourceManagerImpl/installCompiledResourceBundle()
 at mx.resources::ResourceManagerImpl/installCompiledResourceBundles()
 at mx.core::FlexModuleFactory/installCompiledResourceBundles()
 at mx.core::FlexModuleFactory/docFrameHandler()
 at mx.core::FlexModuleFactory/docFrameListener()

The resouce bundle 'mesaging' is included in rpc, and 'rpc' has been loaded to 'caching' while open my app. I found some workround on net, but none does work. I tried:

1.add [ ResourceBundle( "messaging" )]
2.decalare a usage to class that maybe use the 'mesaging', such as
 import mx.messaging.channels.HTTPChannel;
 private var httpChannel:HTTPChannel;</pre>
3.In pom
    <includeResourceBundles>
    <bundle>messaging</bundle>
    </includeResourceBundles>

Anybody has other solution about the problem? Thanks