diff --git a/src/Symfony/Component/Form/Extension/Core/EventListener/ResizeFormListener.php b/src/Symfony/Component/Form/Extension/Core/EventListener/ResizeFormListener.php
index d2b13e4a96..f1c39db245 100644
--- a/src/Symfony/Component/Form/Extension/Core/EventListener/ResizeFormListener.php
+++ b/src/Symfony/Component/Form/Extension/Core/EventListener/ResizeFormListener.php
@@ -139,21 +139,9 @@ class ResizeFormListener implements EventSubscriberInterface
         // The data mapper only adds, but does not remove items, so do this
         // here
         if ($this->allowDelete) {
-            if ($data instanceof \IteratorAggregate) {
-                $iter = $data->getIterator();
-                while ($iter->valid()) {
-                    $name = $iter->key();
-                    if ($form->has($name)) {
-                        $iter->next();
-                    } else {
-                        $iter->offsetUnset($name);
-                    }
-                }
-            } else {
-                foreach ($data as $name => $child) {
-                    if (!$form->has($name)) {
-                        unset($data[$name]);
-                    }
+            foreach ($data as $name => $child) {
+                if (!$form->has($name)) {
+                    unset($data[$name]);
                 }
             }
         }
diff --git a/src/Symfony/Component/Form/Tests/Extension/Core/EventListener/ResizeFormListenerTest.php b/src/Symfony/Component/Form/Tests/Extension/Core/EventListener/ResizeFormListenerTest.php
index 1367b3ef02..3c162654dd 100644
--- a/src/Symfony/Component/Form/Tests/Extension/Core/EventListener/ResizeFormListenerTest.php
+++ b/src/Symfony/Component/Form/Tests/Extension/Core/EventListener/ResizeFormListenerTest.php
@@ -11,6 +11,7 @@
 
 namespace Symfony\Component\Form\Tests\Extension\Core\EventListener;
 
+use Doctrine\Common\Collections\ArrayCollection;
 use Symfony\Component\Form\Extension\Core\EventListener\ResizeFormListener;
 use Symfony\Component\Form\FormBuilder;
 use Symfony\Component\Form\FormEvent;
@@ -252,4 +253,17 @@ class ResizeFormListenerTest extends \PHPUnit_Framework_TestCase
 
         $this->assertEquals(array(), $event->getData());
     }
+
+    public function testOnSubmitDealsWithIteratorAggregate()
+    {
+        $this->form->add($this->getForm('1'));
+
+        $data = new ArrayCollection(array(0 => 'first', 1 => 'second', 2 => 'third'));
+        $event = new FormEvent($this->form, $data);
+        $listener = new ResizeFormListener('text', array(), false, true);
+        $listener->onSubmit($event);
+
+        $this->assertArrayNotHasKey(0, $event->getData());
+        $this->assertArrayNotHasKey(2, $event->getData());
+    }
 }