diff --git a/addons/account/account_move_line.py b/addons/account/account_move_line.py
index 69a62c9d5de..3e40840ff88 100644
--- a/addons/account/account_move_line.py
+++ b/addons/account/account_move_line.py
@@ -1202,7 +1202,7 @@ class account_move_line(osv.osv):
                         break
             # Automatically convert in the account's secondary currency if there is one and
             # the provided values were not already multi-currency
-            if account.currency_id and (vals.get('amount_currency', False) is False) and account.currency_id.id != account.company_id.currency_id.id:
+            if account.currency_id and 'amount_currency' not in vals and account.currency_id.id != account.company_id.currency_id.id:
                 vals['currency_id'] = account.currency_id.id
                 ctx = {}
                 if 'date' in vals: