diff --git a/addons/account_anglo_saxon/purchase.py b/addons/account_anglo_saxon/purchase.py
index f08cc0879a5..6bda54dbe17 100644
--- a/addons/account_anglo_saxon/purchase.py
+++ b/addons/account_anglo_saxon/purchase.py
@@ -30,7 +30,7 @@ class purchase_order(osv.osv):
         line = super(purchase_order, self)._prepare_inv_line(cr, uid, account_id, order_line, context=context)
         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:
+            if not acc_id:
                 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