In case you’re wondering where Flex Builder installs the Flex framework .as source files here’s a snapshot:

And Here’s a path to copy and paste (based on the moxie beta):
/Applications/Adobe Flex Builder 3 Plug-in/sdks/moxie/frameworks/projects/framework/src
One Comment
Is this where it pulls source when you use Flex Builder’s “Create Actionscript File” ?? I’m looking to edit those templates.