diff --git a/account_credit_control/invoice.py b/account_credit_control/invoice.py
index a8e90f024..d361f7a2e 100644
--- a/account_credit_control/invoice.py
+++ b/account_credit_control/invoice.py
@@ -18,7 +18,7 @@
 #    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #
 ##############################################################################
-from openerp.osv import orm
+from openerp.osv import orm, fields
 from openerp.tools.translate import _