diff --git a/lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php b/lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php
index 4057455b3..b5eebcdde 100644
--- a/lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php
+++ b/lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php
@@ -29,7 +29,6 @@ use ReflectionClass;
 use Doctrine\Common\Persistence\Mapping\ClassMetadata;
 use Doctrine\Common\ClassLoader;
 use Doctrine\ORM\Cache\CacheException;
-use Doctrine\ORM\Cache\AssociationCacheEntry;
 
 /**
  * A <tt>ClassMetadata</tt> instance holds all the object-relational mapping metadata
@@ -715,14 +714,11 @@ class ClassMetadataInfo implements ClassMetadata
      */
     public function getIdentifierValues($entity)
     {
-        if ($entity instanceof AssociationCacheEntry) {
-            throw new \InvalidArgumentException('WTF DUDE: ' . $entity->class . ' - ' . \serialize($entity->identifier));
-        }
         if ($this->isIdentifierComposite) {
             $id = [];
 
             foreach ($this->identifier as $idField) {
-                $value = $this->getIndentifierValue($entity, $idField);
+                $value = $this->reflFields[$idField]->getValue($entity);
 
                 if (null !== $value) {
                     $id[$idField] = $value;
@@ -733,7 +729,7 @@ class ClassMetadataInfo implements ClassMetadata
         }
 
         $id = $this->identifier[0];
-        $value = $this->getIndentifierValue($entity, $id);
+        $value = $this->reflFields[$id]->getValue($entity);
 
         if (null === $value) {
             return [];
@@ -742,15 +738,6 @@ class ClassMetadataInfo implements ClassMetadata
         return [$id => $value];
     }
 
-    private function getIndentifierValue($entity, $id)
-    {
-        if ($entity instanceof AssociationCacheEntry) {
-             return $entity->identifier[$id];
-        }
-
-        return $this->reflFields[$id]->getValue($entity);
-    }
-
     /**
      * Populates the entity identifier of an entity.
      *