diff --git a/tests/unicode.lisp b/tests/unicode.lisp
index f863e3181146d2c1a691f359036f54c51705e63a..16c0c77f4b657a7114a6b2e0421f3f11d7247961 100644
--- a/tests/unicode.lisp
+++ b/tests/unicode.lisp
@@ -171,7 +171,7 @@
 (define-test unicode.word-break
   "Test Unicode word break algorithm"
   (:tag :unicode)
-  (with-open-file (s *word-break-test* :direction :input :external-format :utf)
+  (with-open-file (s *word-break-test* :direction :input :external-format :utf-8)
     (loop for line = (read-line s nil nil)
 	  while line
 	  do