diff --git a/lib/Doctrine/ORM/PersistentCollection.php b/lib/Doctrine/ORM/PersistentCollection.php
index 134deb695..5eb139628 100644
--- a/lib/Doctrine/ORM/PersistentCollection.php
+++ b/lib/Doctrine/ORM/PersistentCollection.php
@@ -177,9 +177,7 @@ final class PersistentCollection implements \Doctrine\Common\Collections\Collect
      */
     public function hydrateAdd($element)
     {
-        if ( ! $this->contains($element)) {
-            $this->_coll->add($element);
-        }
+        $this->_coll->add($element);
         
         // If _backRefFieldName is set, then the association is bidirectional
         // and we need to set the back reference.
@@ -206,9 +204,7 @@ final class PersistentCollection implements \Doctrine\Common\Collections\Collect
      */
     public function hydrateSet($key, $element)
     {
-        if ( ! $this->contains($element)) {
-            $this->_coll->set($key, $element);
-        }
+        $this->_coll->set($key, $element);
         
         // If _backRefFieldName is set, then the association is bidirectional
         // and we need to set the back reference.
diff --git a/lib/Doctrine/ORM/UnitOfWork.php b/lib/Doctrine/ORM/UnitOfWork.php
index c65acdeba..e6ac73794 100644
--- a/lib/Doctrine/ORM/UnitOfWork.php
+++ b/lib/Doctrine/ORM/UnitOfWork.php
@@ -451,13 +451,10 @@ class UnitOfWork implements PropertyChangedListener
                 $actualData[$name] = $refProp->getValue($entity);
             }
 
-            if ($class->isCollectionValuedAssociation($name) && $actualData[$name] !== null) {
+            if ($class->isCollectionValuedAssociation($name) && $actualData[$name] !== null
+                    && ! ($actualData[$name] instanceof PersistentCollection)) {
                 // If $actualData[$name] is Collection then unwrap the array
                 if ( ! $actualData[$name] instanceof ArrayCollection) {
-                    if ($actualData[$name] instanceof PersistentCollection) {
-                        $actualData[$name] = $actualData[$name]->toArray();
-                    }
-                    
                     $actualData[$name] = new ArrayCollection($actualData[$name]);
                 }
                 
@@ -1136,8 +1133,9 @@ class UnitOfWork implements PropertyChangedListener
 
         $visited[$oid] = $entity; // Mark visited
 
-        $class = $this->_em->getClassMetadata(get_class($entity));      
-        $entityState = $this->getEntityState($entity, self::STATE_NEW);  
+        $class = $this->_em->getClassMetadata(get_class($entity));
+        $entityState = $this->getEntityState($entity, self::STATE_NEW);
+        
         switch ($entityState) {
             case self::STATE_MANAGED:
                 // Nothing to do, except if policy is "deferred explicit"
diff --git a/tests/Doctrine/Tests/ORM/Functional/StandardEntityPersisterTest.php b/tests/Doctrine/Tests/ORM/Functional/StandardEntityPersisterTest.php
index 2807be4e6..88b4a9098 100644
--- a/tests/Doctrine/Tests/ORM/Functional/StandardEntityPersisterTest.php
+++ b/tests/Doctrine/Tests/ORM/Functional/StandardEntityPersisterTest.php
@@ -3,7 +3,7 @@
 namespace Doctrine\Tests\ORM\Functional;
 
 use Doctrine\Tests\Models\ECommerce\ECommerceCart,
-    Doctrine\Tests\Models\ECommerce\ECommerceCategory,
+    Doctrine\Tests\Models\ECommerce\ECommerceFeature,
     Doctrine\Tests\Models\ECommerce\ECommerceCustomer,
     Doctrine\Tests\Models\ECommerce\ECommerceProduct;
     
@@ -48,31 +48,40 @@ class StandardEntityPersisterTest extends \Doctrine\Tests\OrmFunctionalTestCase
      */
     public function testAddPersistRetrieve()
     {
-        $category = new ECommerceCategory();
-        $category->setName('Eletronics');
-        
-        $product = new ECommerceProduct();
-        $product->setName('MP3 Player Foo');
-        $category->addProduct($product);
-        
-        $product2 = new ECommerceProduct();
-        $product2->setName('MP3 Player Bar');
-        $category->addProduct($product2);
-        
-        $this->_em->persist($category);
+        $f1 = new ECommerceFeature;
+        $f1->setDescription('AC-3');
+
+        $f2 = new ECommerceFeature;
+        $f2->setDescription('DTS');
+
+        $p = new ECommerceProduct;
+        $p->addFeature($f1);
+        $p->addfeature($f2);
+        $this->_em->persist($p);
+
         $this->_em->flush();
         
-        // He reported that using $this->_em->clear(); after flush fixes the problem.
-        // It should work out of the box. That's what we are testing.
+        $this->assertEquals(2, count($p->getFeatures()));
+        $this->assertTrue($p->getFeatures() instanceof \Doctrine\ORM\PersistentCollection);
+
+        $q = $this->_em->createQuery(
+            'SELECT p, f
+               FROM Doctrine\Tests\Models\ECommerce\ECommerceProduct p
+               JOIN p.features f'
+        );
         
-        $q = $this->_em->createQuery('
-            SELECT c, p 
-              FROM Doctrine\Tests\Models\ECommerce\ECommerceCategory c 
-              LEFT JOIN c.products p
-        ');
         $res = $q->getResult();
         
-        $this->assertEquals(1, count($res));
-        $this->assertEquals(2, count($res[0]->getProducts()));
+        $this->assertEquals(2, count($p->getFeatures()));
+        $this->assertTrue($p->getFeatures() instanceof \Doctrine\ORM\PersistentCollection);
+        
+        // Check that the features are the same instances still
+        foreach ($p->getFeatures() as $feature) {
+            if ($feature->getDescription() == 'AC-3') {
+                $this->assertTrue($feature === $f1);
+            } else {
+                $this->assertTrue($feature === $f2);
+            }
+        }
     }
 }