Using Native Extensions with Flex SDK 4.6.0

Hi,

I'm trying to get the Mac OSX Hello World example working with Flex SDK 4.6.0. I've changed over all of the places where it has 4.5.1/ etc, got the XCode project to compile properly, but I've got stumped on a problem on step 3. The output I get at the end of step 3 is:

+ '/Applications/Adobe Flash Builder 4.6/sdks/4.6.0/bin/adt' -package -storetype PKCS12 -keystore src/assets/test.pfx -storepass none -target ane airrt.ane src/extension.xml -swc src/assets/com.airrt.extensions.swc -platform MacOS-x86 -C src/assets/platform/mac .

Invalid swc file. The extension NameSpace requires the SWF verison to be 13 or lower.

/Users/owenbennett/Documents/Projects/Flash/Native Extensions OSX/NativeExtensions

Any ideas?

Thanks,

Owen