diff --git a/README_os390.txt b/README_os390.txt
index f4e6736..5c98c91 100644
--- a/README_os390.txt
+++ b/README_os390.txt
@@ -1,4 +1,4 @@
-README_zOS.txt for version 7.3 of Vim: Vi IMproved.
+README_zOS.txt for version 7.3b of Vim: Vi IMproved.
 
 This readme explains how to build Vim on z/OS.  Formerly called OS/390.
 See "README.txt" for general information about Vim.