diff --git a/src/vnet/session/application_worker.c b/src/vnet/session/application_worker.c
index a806c4a..960d916 100644
--- a/src/vnet/session/application_worker.c
+++ b/src/vnet/session/application_worker.c
@@ -369,7 +369,7 @@
 {
   session_event_t evt = { .event_type = SESSION_CTRL_EVT_BOUND,
 			  .as_u64[0] = alsh,
-			  .as_u64[1] = (u64) opaque << 32 | err };
+			  .as_u64[1] = (u64) opaque << 32 | (u32) err };
 
   app_worker_add_event_custom (app_wrk, 0 /* thread index */, &evt);