First step in the Vim 7.3 branch.  Changed version numbers.
diff --git a/README_srcdos.txt b/README_srcdos.txt
index d525619..39e72fe 100644
--- a/README_srcdos.txt
+++ b/README_srcdos.txt
@@ -1,4 +1,4 @@
-README_srcdos.txt for version 7.2 of Vim: Vi IMproved.
+README_srcdos.txt for version 7.3a of Vim: Vi IMproved.
 
 See "README.txt" for general information about Vim.
 See "README_dos.txt" for installation instructions for MS-DOS and MS-Windows.