diff --git a/libs/sofia-sip/libsofia-sip-ua/nta/nta_tag.c b/libs/sofia-sip/libsofia-sip-ua/nta/nta_tag.c
index 91ee4b9455..7b46e68ae3 100644
--- a/libs/sofia-sip/libsofia-sip-ua/nta/nta_tag.c
+++ b/libs/sofia-sip/libsofia-sip-ua/nta/nta_tag.c
@@ -405,8 +405,8 @@ tag_typedef_t ntatag_maxsize = USIZETAG_TYPEDEF(maxsize);
* Maximum size of proceeding queue.
*
* If the size of the proceedng message queue would exceed the
- * given limit, the stack will automatically respond with 486
- * Server Busy.
+ * given limit, the stack will automatically respond with 503
+ * Service Unavailable.
*
* @par Used with
* nua_create(), nua_set_params(),