When creating an Android app using PhoneGap Build, how can I prevent the system from adding the menu button at the bottom of the screen?

From Disabling menu button in Android using PhoneGap, I got that when using pure PhoneGap, the solution appears to be to comment out the onCreateOptionsMenu function in MainActivity.java. However, when using PhoneGap Build, I obviously do not have access to any java files.
So what is the solution for PhoneGap Build?
- Is there a special option that needs to be set in the config.xml?
- Can it be disabled via the JavaScript event handler for the menu button?
- Any other ideas?