Daniel Cousineau has posted a "quickie" over on his blog today dealing with error controllers in a Zend Framework application.

In my quest to do some alterations on ZF error handling (in particular, render the view if the action or controller is not found, makes it real easy for my designer to prototype) I had the desire to be able to allow modules to have their own ErrorControllers. Unfortunately, the Zend_Controller_Plugin_ErrorHandler() default does not allow for this and I didn't really want to extend that class (I planned on handling the rendering in the ErrorControllers) so I wrote up a quick plugin.

His plugin (code included in the post) hooks into the routeShutdown part of the routing process and overrides the default error handler for the module to pass the request off to his custom one.