diff --git a/lib/Doctrine/Transaction.php b/lib/Doctrine/Transaction.php
index baf03c9db..93bf4f36b 100644
--- a/lib/Doctrine/Transaction.php
+++ b/lib/Doctrine/Transaction.php
@@ -372,7 +372,7 @@ class Doctrine_Transaction extends Doctrine_Connection_Module
                     }
     
                     // take snapshots of all collections used within this transaction
-                    foreach (array_unique($this->_collections) as $coll) {
+                    foreach ($this->_collections as $coll) {
                         $coll->takeSnapshot();
                     }
                     $this->_collections = array();