Actually I'm not sure if this is in the manual, but last week I briefly tried to use the latest version of Chris Scott's Swiz framework for flex from SVN. When I couldn't get it to work I went back to the latest SWC release that I had. Last night I randomly stumbled on an introduction to Swiz that Chris did mentioning build arguments required.
So in short, if your building Swiz from source (or plan on it) don't forget to add the following line of code to the Swiz project compiler:
-keep-as3-metadata+=Autowire,Mediate,Event