David Stockton has a new tutorial posted to his blog - a technique he's found useful in his Zend Framework application to make the ErrorController work with Ajax calls to reduce the message you get back to just a JSON response.

If you've ever built a Zend Framework MVC app which makes AJAX calls, you may have noticed that if an error occurs, you'll get a chunk of JSON followed by the HTML for the error page. If you've built a layout, you'll get all of that back to. This is fine if your users hit the page in the browser but it can cause problems with your JavaScript being able to correctly decode your JSON.

The fix is pretty simple, though, and only requires that you add the error handling action to the Ajax context to force it to drop the layout and any other HTML that might come along with the view. He includes a bit more code to have the error handler include the exceptions and pass them out to be included in the JSON response.