Protecting code against decompilers (obfuscation) in Adobe Flash Builder 4.7

Hello,

I created an Air application SWF file with the Air SDK 3.4 with Adobe Flash Builder 4.7. I'm trying to use Sothink SWF Decompiler 7.4 to check if I can look at the code (without doing any obfuscation with another tool).  It seems that I can see the code of the debug version of the SWF file, but I can't see the code for the release version of the SWF file.

Now, my question: is the released SWF file already protected against decompilers?  I know that previous version of Adobe Flex Builder was not and required the use of an obfuscation software.  I would like to make sure that the code can't be read before releasing only.

Thanks for your input.