If you need to work with action script in flash and flex, you may have used the build-in debugger for logging your trace message.
But the build-in debugger is not good to read.
Today, i find a logger seem suit my need. It is called ThunderBolt AS3, which is a lightweight logger extension for Flex 3-4, AIR and Flash 9-10 applications.
It can log your message with firebug or the ThunderBolt AS3 Console
1. Support logging to firebug console
2. Logging of package names + class names + code line numbers
3. With ThunderBolt AS3 Console air application
Check more about the new version.