diff --git a/.travis.yml b/.travis.yml
index adbf643c2..2119b575c 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,6 +4,7 @@ php:
   - 5.3
   - 5.4
   - 5.5
+  - 5.6
 
 env:
   - DB=mysql
diff --git a/lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php b/lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php
index 4880055b3..88c905baf 100644
--- a/lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php
+++ b/lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php
@@ -866,7 +866,7 @@ class ClassMetadataInfo implements ClassMetadata
     public function newInstance()
     {
         if ($this->_prototype === null) {
-            if (PHP_VERSION_ID === 50429 || PHP_VERSION_ID === 50513) {
+            if (PHP_VERSION_ID === 50429 || PHP_VERSION_ID === 50513 || PHP_VERSION_ID >= 50600) {
                 $this->_prototype = $this->reflClass->newInstanceWithoutConstructor();
             } else {
                 $this->_prototype = unserialize(sprintf('O:%d:"%s":0:{}', strlen($this->name), $this->name));
diff --git a/tests/Doctrine/Tests/ORM/Mapping/ClassMetadataTest.php b/tests/Doctrine/Tests/ORM/Mapping/ClassMetadataTest.php
index aa284db89..9c1ea3e6c 100644
--- a/tests/Doctrine/Tests/ORM/Mapping/ClassMetadataTest.php
+++ b/tests/Doctrine/Tests/ORM/Mapping/ClassMetadataTest.php
@@ -1101,6 +1101,31 @@ class ClassMetadataTest extends \Doctrine\Tests\OrmTestCase
 
         $this->assertFalse($class->isIdentifier('foo'));
     }
+
+    /**
+     * @group DDC-3120
+     */
+    public function testCanInstantiateInternalPhpClassSubclass()
+    {
+        $classMetadata = new ClassMetadata(__NAMESPACE__ . '\\MyArrayObjectEntity');
+
+        $classMetadata->initializeReflection(new \Doctrine\Common\Persistence\Mapping\RuntimeReflectionService);
+
+        $this->assertInstanceOf(__NAMESPACE__ . '\\MyArrayObjectEntity', $classMetadata->newInstance());
+    }
+
+    /**
+     * @group DDC-3120
+     */
+    public function testCanInstantiateInternalPhpClassSubclassFromUnserializedMetadata()
+    {
+        /* @var $classMetadata ClassMetadata */
+        $classMetadata = unserialize(serialize(new ClassMetadata(__NAMESPACE__ . '\\MyArrayObjectEntity')));
+
+        $classMetadata->wakeupReflection(new \Doctrine\Common\Persistence\Mapping\RuntimeReflectionService);
+
+        $this->assertInstanceOf(__NAMESPACE__ . '\\MyArrayObjectEntity', $classMetadata->newInstance());
+    }
 }
 
 /**
@@ -1137,3 +1162,7 @@ class MyPrefixNamingStrategy extends \Doctrine\ORM\Mapping\DefaultNamingStrategy
         return strtolower($this->classToTableName($className)) . '_' . $propertyName;
     }
 }
+
+class MyArrayObjectEntity extends \ArrayObject
+{
+}