diff --git a/lib/Doctrine/ORM/AbstractQuery.php b/lib/Doctrine/ORM/AbstractQuery.php
index 6dda4d2f8..be1a0a1fb 100644
--- a/lib/Doctrine/ORM/AbstractQuery.php
+++ b/lib/Doctrine/ORM/AbstractQuery.php
@@ -296,12 +296,31 @@ abstract class AbstractQuery
      */
     public function setResultSetMapping(Query\ResultSetMapping $rsm)
     {
-        $rsm->translateNamespaces($this->_em);
+        $this->translateNamespaces($rsm);
         $this->_resultSetMapping = $rsm;
 
         return $this;
     }
 
+    /**
+     * Allows to translate entity namespaces to full qualified names.
+     *
+     * @param EntityManager $em
+     *
+     * @return void
+     */
+    private function translateNamespaces(Query\ResultSetMapping $rsm)
+    {
+        $entityManager = $this->_em;
+
+        $translate = function ($alias) use ($entityManager) {
+            return $entityManager->getClassMetadata($alias)->getName();
+        };
+
+        $rsm->aliasMap = array_map($translate, $rsm->aliasMap);
+        $rsm->declaringClasses = array_map($translate, $rsm->declaringClasses);
+    }
+
     /**
      * Set a cache profile for hydration caching.
      *
diff --git a/lib/Doctrine/ORM/Query/ResultSetMapping.php b/lib/Doctrine/ORM/Query/ResultSetMapping.php
index 1461f4f4c..50dacea41 100644
--- a/lib/Doctrine/ORM/Query/ResultSetMapping.php
+++ b/lib/Doctrine/ORM/Query/ResultSetMapping.php
@@ -19,8 +19,6 @@
 
 namespace Doctrine\ORM\Query;
 
-use Doctrine\ORM\EntityManager;
-
 /**
  * A ResultSetMapping describes how a result set of an SQL query maps to a Doctrine result.
  *
@@ -545,27 +543,5 @@ class ResultSetMapping
 
         return $this;
     }
-
-    /**
-     * Allows to translate entity namespaces to full qualified names.
-     *
-     * @param EntityManager $em
-     *
-     * @return void
-     */
-    public function translateNamespaces(EntityManager $em)
-    {
-        $fqcn = array();
-
-        $translate = function (&$alias) use ($em, &$fqcn) {
-            if ( ! isset($fqcn[$alias])) {
-                $fqcn[$alias] = $em->getClassMetadata($alias)->getName();
-            }
-            $alias = $fqcn[$alias];
-        };
-
-        array_walk($this->aliasMap, $translate);
-        array_walk($this->declaringClasses, $translate);
-    }
 }