diff --git a/pkgs/racket-test-core/tests/racket/sync.rktl b/pkgs/racket-test-core/tests/racket/sync.rktl
index 51e27d4ab5..c9179e96ab 100644
--- a/pkgs/racket-test-core/tests/racket/sync.rktl
+++ b/pkgs/racket-test-core/tests/racket/sync.rktl
@@ -1439,6 +1439,25 @@
   (try (lambda (c) (choice-evt c (alarm-evt (+ 10000 (current-inexact-milliseconds)))))
        'ok-channel+alarm))
 
+;; ----------------------------------------
+;; Make sure that suspending a thread that's blocked on a
+;; semaphore works right when the semaphore becomes available
+;; before the thread is resumed
+
+(let ()
+  (define s (make-semaphore))
+  (define v #f)
+  (define t (thread
+             (lambda ()
+               (set! v (sync (wrap-evt s (lambda (v) 'ok)))))))
+  (sync (system-idle-evt))
+  (thread-suspend t)
+  (sync (system-idle-evt))
+  (semaphore-post s)
+  (thread-resume t)
+  (void (sync t))
+  (test 'ok values v))
+
 ;; ----------------------------------------
 
 (report-errs)
diff --git a/racket/src/racket/src/sema.c b/racket/src/racket/src/sema.c
index 90e9628fc9..6e4d597d79 100644
--- a/racket/src/racket/src/sema.c
+++ b/racket/src/racket/src/sema.c
@@ -848,7 +848,7 @@ int scheme_wait_semas_chs(int n, Scheme_Object **o, int just_try, Syncing *synci
 	    if (ws[i]->in_line)
 	      get_outof_line(semas[i], ws[i]);
 	  }
-	  
+
 	  scheme_thread_block(0); /* ok if it returns multiple times */ 
 	  scheme_current_thread->ran_some = 1;
 	  /* [but why would it return multiple times?! there must have been a reason...] */
@@ -910,8 +910,11 @@ int scheme_wait_semas_chs(int n, Scheme_Object **o, int just_try, Syncing *synci
 	    if (semas[i]->value) {
 	      if ((semas[i]->value > 0) && (!syncing || !syncing->reposts || !syncing->reposts[i]))
 		--semas[i]->value;
-              if (syncing && syncing->accepts && syncing->accepts[i])
-                scheme_accept_sync(syncing, i);
+              if (syncing) {
+                syncing->result = i + 1;
+                if (syncing->accepts && syncing->accepts[i])
+                  scheme_accept_sync(syncing, i);
+              }
 	      break;
 	    }
 	  }  else if (semas[i]->so.type == scheme_never_evt_type) {