Allow to set arbitrary status code for Exception strategy

library/Zend/Mvc/View/Http/ExceptionStrategy.php

@@ -158,9 +158,10 @@ public function prepareExceptionViewModel(MvcEvent $e)
                 $response = $e->getResponse();
                 if (!$response) {
                     $response = new HttpResponse();
+                    $response->setStatusCode(500);
                     $e->setResponse($response);
                 }
-                $response->setStatusCode(500);
+                $response->setStatusCode($response->getStatusCode());
                 break;
         }
     }

tests/ZendTest/Mvc/View/ExceptionStrategyTest.php

@@ -169,4 +169,25 @@ public function testDetachesListeners()
         $listeners = $events->getListeners(MvcEvent::EVENT_DISPATCH_ERROR);
         $this->assertEquals(0, count($listeners));
     }
+
+    public function testReuseResponseStatusCodeIfItExists()
+    {
+        $event = new MvcEvent();
+        $response = new Response();
+        $response->setStatusCode(401);
+        $event->setResponse($response);
+        $this->strategy->prepareExceptionViewModel($event);
+        $response = $event->getResponse();
+        if (null !== $response) {
+            $this->assertEquals(401, $response->getStatusCode());
+        }
+        $model = $event->getResult();
+        if (null !== $model) {
+            $variables = $model->getVariables();
+            $this->assertArrayNotHasKey('message', $variables);
+            $this->assertArrayNotHasKey('exception', $variables);
+            $this->assertArrayNotHasKey('display_exceptions', $variables);
+            $this->assertNotEquals('error', $model->getTemplate());
+        }
+    }
 }