I believe the Android SDK has tools that let you take an APK apart and put it back together. You would then be able to make changes to the manifest. You will have to sign the .apk after any modifications, I suspect.
Thank you for the question regarding AIR on Android. If you haven't already, I'd like to encourage you to http://www.adobe.com/go/airbetasignup. Once you sign up, you should get immediate access to the Android prerelease program where you'll find forums specifically geared towards Android development.