diff --git a/composer.json b/composer.json
index 95f128243..7ce97be8a 100644
--- a/composer.json
+++ b/composer.json
@@ -30,8 +30,10 @@
         "symfony/process": "~2.1"
     },
     "require-dev": {
-        "phpunit/phpunit": "~4.5"
+        "phpunit/phpunit": "~4.5",
+        "phpunit/phpunit-mock-objects": "2.3.0"
     },
+    "_": "phpunit/phpunit-mock-objects required in 2.3.0 due to https://github.com/sebastianbergmann/phpunit-mock-objects/issues/223",
     "config": {
         "platform": {
             "php": "5.3.3"
diff --git a/composer.lock b/composer.lock
index d60efddb4..b5c4f49e8 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at http://getcomposer.org/doc/01-basic-usage.md#composer-lock-the-lock-file",
         "This file is @generated automatically"
     ],
-    "hash": "f81f79c547e147bfef2b15c1aed19f08",
+    "hash": "9a6a4c54f625e54ffe83b995dd796620",
     "packages": [
         {
             "name": "justinrainbow/json-schema",
@@ -761,25 +761,25 @@
         },
         {
             "name": "phpunit/phpunit-mock-objects",
-            "version": "2.3.1",
+            "version": "2.3.0",
             "source": {
                 "type": "git",
                 "url": "https://github.com/sebastianbergmann/phpunit-mock-objects.git",
-                "reference": "74ffb87f527f24616f72460e54b595f508dccb5c"
+                "reference": "c63d2367247365f688544f0d500af90a11a44c65"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/sebastianbergmann/phpunit-mock-objects/zipball/74ffb87f527f24616f72460e54b595f508dccb5c",
-                "reference": "74ffb87f527f24616f72460e54b595f508dccb5c",
+                "url": "https://api.github.com/repos/sebastianbergmann/phpunit-mock-objects/zipball/c63d2367247365f688544f0d500af90a11a44c65",
+                "reference": "c63d2367247365f688544f0d500af90a11a44c65",
                 "shasum": ""
             },
             "require": {
-                "doctrine/instantiator": "~1.0,>=1.0.2",
+                "doctrine/instantiator": "~1.0,>=1.0.1",
                 "php": ">=5.3.3",
                 "phpunit/php-text-template": "~1.2"
             },
             "require-dev": {
-                "phpunit/phpunit": "~4.4"
+                "phpunit/phpunit": "~4.3"
             },
             "suggest": {
                 "ext-soap": "*"
@@ -812,7 +812,7 @@
                 "mock",
                 "xunit"
             ],
-            "time": "2015-04-02 05:36:41"
+            "time": "2014-10-03 05:12:11"
         },
         {
             "name": "sebastian/comparator",