diff --git a/src/kernel/message.c b/src/kernel/message.c
index 7937927b..7dbcc2a8 100644
--- a/src/kernel/message.c
+++ b/src/kernel/message.c
@@ -953,6 +953,14 @@ checkagain:
             sem_wait (&pMsgQueue->wait);
         }
 
+        goto checkagain;
+    }
+    else {
+        /* no message, wait again. */
+        if (pMsgQueue->OnIdle && !pMsgQueue->OnIdle (pMsgQueue, FALSE)) {
+            handle_idle_message (pMsgQueue);
+        }
+
         goto checkagain;
     }
 #else   /* defined _MGHAVE_VIRTUAL_WINDOW */
@@ -964,6 +972,11 @@ checkagain:
         }
         goto checkagain;
     }
+    else {
+        if (!pMsgQueue->OnIdle (pMsgQueue, TRUE)) {
+            handle_idle_message (pMsgQueue);
+        }
+    }
 #endif  /* not defined _MGHAVE_VIRTUAL_WINDOW */
 
     /* no message */