diff --git a/server/queue.c b/server/queue.c
index f6d6ca4..320bdb0 100644
--- a/server/queue.c
+++ b/server/queue.c
@@ -407,7 +407,7 @@
     if (!ptr) return 0;
     prev = LIST_ENTRY( ptr, struct message, entry );
     if (prev->result) return 0;
-    if (prev->win != msg->win) return 0;
+    if (prev->win && msg->win && prev->win != msg->win) return 0;
     if (prev->msg != msg->msg) return 0;
     if (prev->type != msg->type) return 0;
     /* now we can merge it */