diff --git a/lib/Doctrine/ORM/PersistentCollection.php b/lib/Doctrine/ORM/PersistentCollection.php
index 947774542..462c23ec7 100644
--- a/lib/Doctrine/ORM/PersistentCollection.php
+++ b/lib/Doctrine/ORM/PersistentCollection.php
@@ -587,6 +587,8 @@ final class PersistentCollection implements Collection, Selectable
      */
     public function add($value)
     {
+        $this->initialize();
+
         $this->coll->add($value);
 
         $this->changed();
@@ -757,6 +759,8 @@ final class PersistentCollection implements Collection, Selectable
      */
     public function key()
     {
+        $this->initialize();
+
         return $this->coll->key();
     }
 
@@ -765,6 +769,8 @@ final class PersistentCollection implements Collection, Selectable
      */
     public function current()
     {
+        $this->initialize();
+
         return $this->coll->current();
     }
 
@@ -773,6 +779,8 @@ final class PersistentCollection implements Collection, Selectable
      */
     public function next()
     {
+        $this->initialize();
+        
         return $this->coll->next();
     }