diff --git a/composer/schema/grid/field.py b/composer/schema/grid/field.py
index 2188d7e..78f57a2 100644
--- a/composer/schema/grid/field.py
+++ b/composer/schema/grid/field.py
@@ -1,5 +1,5 @@
 #
-#  Copyright (c) 2011 Helmut Merz helmutm@cy55.de
+#  Copyright (c) 2013 Helmut Merz helmutm@cy55.de
 #
 #  This program is free software; you can redistribute it and/or modify
 #  it under the terms of the GNU General Public License as published by
@@ -148,7 +148,7 @@ class RecordsFieldInstance(GridFieldInstance):
         if not value:
             value = []
         result = []
-        oldValue = getattr(self.clientContext, self.name, [])
+        oldValue = getattr(self.clientContext, self.name, None) or []
         for idx, row in enumerate(value):
             item = self.unmarshallRow(row, idx)
             if item: