diff --git a/impl/src/main/java/org/glassfish/soteria/mechanisms/openid/controller/AuthenticationController.java b/impl/src/main/java/org/glassfish/soteria/mechanisms/openid/controller/AuthenticationController.java
index 03d03c3..21881a9 100644
--- a/impl/src/main/java/org/glassfish/soteria/mechanisms/openid/controller/AuthenticationController.java
+++ b/impl/src/main/java/org/glassfish/soteria/mechanisms/openid/controller/AuthenticationController.java
@@ -124,7 +124,7 @@ public AuthenticationStatus authenticateUser(HttpServletRequest request, HttpSer
 
         configuration.getExtraParameters().forEach(authRequest::queryParam);
 
-        String authUrl = authRequest.toString();
+        String authUrl = authRequest.build().toString();
         LOGGER.log(FINEST, "Redirecting for authentication to {0}", authUrl);
         try {
             response.sendRedirect(authUrl);