How can I find out which version swc/swf was compiled with?

 I am in the process of upgrading my flex project to use flex 3.4.
When I am running the application I get the following error in flex builder console.

[SWF] C:\dev\DiscoAuto\ria\dci-shell\bin-debug\ECUITFlex_ecue_styles.swf - 115,965 bytes after decompression
 method not implemented mx.core::IFlexModuleFactory/mx.core:IFlexModuleFactory::allowInsecureDomain()
   over-binding 0 in mx.core::FlexModuleFactory
accessor not implemented mx.core:IFlexModuleFactory::preloadedRSLs
   over-binding 0 in mx.core::FlexModuleFactory
method not implemented mx.core::IFlexModuleFactory/mx.core:IFlexModuleFactory::allowDomain()
   over-binding 0 in mx.core::FlexModuleFactory
VerifyError: Error #1053: Illegal override of FlexModuleFactory in mx.core.FlexModuleFactory.
      at global$init()

Googling this error I found out that this means that one of my dependencies are not complied with flex 3.4.
How can I can I found out which version swc/swf was compiled with?