diff --git a/tests/mutex-test.scm b/tests/mutex-test.scm
index ee7c2de1..97e24e81 100644
--- a/tests/mutex-test.scm
+++ b/tests/mutex-test.scm
@@ -225,6 +225,18 @@ Slot  Type                           Meaning
      (print "Forcing primordial broke mutex-unlock! result: " r (mutex-specific mux))
      (test-exit 1)))
 
+(let* ((mux (let ((m (make-mutex 'done))) (mutex-lock! m) m))
+       (t (thread-start!
+	   (lambda ()
+	     (print "Waiting for mutex " mux " in " (current-thread))
+	     (let ((r (mutex-lock! mux)))
+	       (print "mutex-lock! succeeded on locked mutex " mux " result " r)
+	       (if r (test-exit 1)))))))
+  (thread-yield!)
+  (thread-suspend! t)
+  (thread-resume! t)
+  (print "Thread " t " now in state " (thread-state t)))
+
 (cond-expand (dribble
 (define-for-syntax count 0)
 (define-syntax trail