First step in the Vim 7.3 branch.  Changed version numbers.
diff --git a/runtime/doc/os_390.txt b/runtime/doc/os_390.txt
index f061638..f0c9c44 100644
--- a/runtime/doc/os_390.txt
+++ b/runtime/doc/os_390.txt
@@ -1,4 +1,4 @@
-*os_390.txt*    For Vim version 7.2.  Last change: 2008 Dec 17
+*os_390.txt*    For Vim version 7.3a.  Last change: 2008 Dec 17
 
 
 		  VIM REFERENCE MANUAL	  by Ralf Schandl