diff --git a/pym/console/application/cert_func.py b/pym/console/application/cert_func.py
index 74533c5..cbd5d5b 100644
--- a/pym/console/application/cert_func.py
+++ b/pym/console/application/cert_func.py
@@ -48,8 +48,9 @@ def client_post_cert(client, clVars, show_info=False):
     result_sid = _result_sid[1].integer
 
     if os.environ.get("DEBUG"):
-        print _("The client uses certificate %s (server ID %s)") % (
-            client.CERT_FILE, result_post_cert[0])
+        print _("The client uses certificate {certfile} "
+                "(server ID {cert_id})").format(
+            certfile=client.CERT_FILE, cert_id=result_post_cert[0])
     if result_post_cert[0] == -4:
         print _("Certificate not found on the server")
         print _("the client uses certificate %s") % client.CERT_FILE