I have a Google Web Toolkit application that I am deploying to Google App Engine. In the deployed application, I am getting a JavaScript error Uncaught TypeError: Cannot read property 'f' of null. This sounds like the JavaScript equivalent of a Java NullPointerException.

The problem is that the GWT JavaScript is obfuscated, so it's impossible to debug in the browser and I can't reproduce the same problem in hosted mode where I could use the Java debugger. I think the reason I'm only seeing the error on the deployed application is that the database I'm using on the GAE server is triggering something differently than the test database I'm using during testing and development.

So, any ideas about the best way to proceed? I've thought of the following things:

• Deploy a non-obsfucated version of my application. Despite a lot of Googling, I can't figure out how to do this using the automatic deploy script provided with the Google Eclipse Plugin. Does anyone know?
• Download and copy my GAE data to the local server
• Somehow point my development code to use the GAE server for data instead of the local test database. This seems like the best idea...

Can anyone suggest how to proceed here?

Finally, is there a way to catch these JavaScript errors on the production server and log them somewhere? Without logging, I won't have anyway to know if my users are having errors that don't occur on the server. The GWT.log() function is automatically stripped out of the production code...