You can create plugin that will examine your request and based on current module sets ErrorController...
<?php
class My_Controller_Plugin_Utilities extends Zend_Controller_Plugin_Abstract
{
public function routeShutdown (Zend_Controller_Request_Abstract $request)
{
$front = Zend_Controller_Front::getInstance();
if (! ($front->getPlugin('Zend_Controller_Plugin_ErrorHandler') instanceof Zend_Controller_Plugin_ErrorHandler))
return;
$error = $front->getPlugin('Zend_Controller_Plugin_ErrorHandler');
$testRequest = new Zend_Controller_Request_HTTP();
$testRequest->setModuleName($request->getModuleName())
->setControllerName($error->getErrorHandlerController())
->setActionName($error->getErrorHandlerAction());
if ($front->getDispatcher()->isDispatchable($testRequest)) {
$error->setErrorHandlerModule($request->getModuleName());
}
}