diff --git a/src/testdir/test64.ok b/src/testdir/test64.ok
index 8ac9e32..4203c8f 100644
--- a/src/testdir/test64.ok
+++ b/src/testdir/test64.ok
@@ -773,6 +773,9 @@
 OK 0 - [ ]\@!\p\%([ ]\@!\p\)*:
 OK 1 - [ ]\@!\p\%([ ]\@!\p\)*:
 OK 2 - [ ]\@!\p\%([ ]\@!\p\)*:
+OK 0 - m\k\+_\@=\%(_\@!\k\)\@<=\k\+e
+OK 1 - m\k\+_\@=\%(_\@!\k\)\@<=\k\+e
+OK 2 - m\k\+_\@=\%(_\@!\k\)\@<=\k\+e
 OK 0 - [[:alpha:]]\{-2,6}
 OK 1 - [[:alpha:]]\{-2,6}
 OK 2 - [[:alpha:]]\{-2,6}