diff --git a/addons/account_anglo_saxon/purchase.py b/addons/account_anglo_saxon/purchase.py
index b172fc11bbb..8e02cc361ef 100644
--- a/addons/account_anglo_saxon/purchase.py
+++ b/addons/account_anglo_saxon/purchase.py
@@ -28,13 +28,13 @@ class purchase_order(osv.osv):
 
     def prepare_inv_line(self, cr, uid, account_id, order_line, context=None):
         line = super(purchase_order, self).prepare_inv_line(cr, uid, account_id, order_line, context=context)
-        if ol.product_id and not ol.product_id.type == 'service':
-            oa = ol.product_id.property_stock_account_input and ol.product_id.property_stock_account_input.id
+        if order_line.product_id and not order_line.product_id.type == 'service':
+            acc_id = order_line.product_id.property_stock_account_input and order_line.product_id.property_stock_account_input.id
             if not oa:
-                oa = ol.product_id.categ_id.property_stock_account_input_categ and ol.product_id.categ_id.property_stock_account_input_categ.id
-            if oa:
-                fpos = ol.order_id.fiscal_position or False
-                a = self.pool.get('account.fiscal.position').map_account(cr, uid, fpos, oa)
-                line.update({'account_id': a})
+                acc_id = order_line.product_id.categ_id.property_stock_account_input_categ and order_line.product_id.categ_id.property_stock_account_input_categ.id
+            if acc_id:
+                fpos = order_line.order_id.fiscal_position or False
+                new_account_id = self.pool.get('account.fiscal.position').map_account(cr, uid, fpos, acc_id)
+                line.update({'account_id': new_account_id})
         return line
 purchase_order()