--- a/Model/DocumentTagInterface.php	Fri Dec 09 04:53:56 2011 +0100
+++ b/Model/DocumentTagInterface.php	Fri Dec 09 06:43:49 2011 +0100
@@ -103,5 +103,11 @@
      */
     function getDocument();
     
+   /**
+    * return the utc time when this object has been created
+    */
+    function getCreatedAt();
+    
+    
 
 }
\ No newline at end of file