Changes for iOS 4.0+. Without that, it was giving error as reported on h...

Fix for https://github.com/StickSports/ANE-In-App-Purchase/issues/5

Also added an option to package ANE without requirement of signing. As faced an error "Unable to build a valid certificate chain for the signer." and found that http://arielsommeria.com/blog/2012/01/25/packaging-air-native-extensions-is-horrible-but-this-might-help/ may help.