diff --git a/eopayment/systempayv2.py b/eopayment/systempayv2.py
index 91a56b9..6ff2b1a 100644
--- a/eopayment/systempayv2.py
+++ b/eopayment/systempayv2.py
@@ -265,11 +265,11 @@ class Payment(PaymentCommon):
                 'required': True, },
             {'name': 'secret_test',
                 'caption': _(u'Secret pour la configuration de TEST'),
-                'validation': lambda value: str.isdigit(value),
+                'validation': lambda value: str.isalnum(value),
                 'required': True, },
             {'name': 'secret_production',
                 'caption': _(u'Secret pour la configuration de PRODUCTION'),
-                'validation': lambda value: str.isdigit(value), },
+                'validation': lambda value: str.isalnum(value), },
             {
                 'name': 'manual_validation',
                 'caption': 'Validation manuelle',