diff --git a/collects/net/cookie-unit.ss b/collects/net/cookie-unit.ss
index 9429fc6..8b5317e 100644
--- a/collects/net/cookie-unit.ss
+++ b/collects/net/cookie-unit.ss
@@ -64,9 +64,10 @@
   ;; constructs a cookie-error struct from the given error message
   ;; (added to fix exceptions-must-take-immutable-strings bug)
   (define (error* fmt . args)
-    (make-cookie-error
-     (string->immutable-string (apply format fmt args))
-     (current-continuation-marks)))
+    (raise
+     (make-cookie-error
+       (string->immutable-string (apply format fmt args))
+       (current-continuation-marks))))
 
   ;; The syntax for the Set-Cookie response header is
   ;; set-cookie      =       "Set-Cookie:" cookies