First step in the Vim 7.3 branch.  Changed version numbers.
diff --git a/runtime/doc/os_win32.txt b/runtime/doc/os_win32.txt
index 6ed5891..8ea7dc1 100644
--- a/runtime/doc/os_win32.txt
+++ b/runtime/doc/os_win32.txt
@@ -1,4 +1,4 @@
-*os_win32.txt*  For Vim version 7.2.  Last change: 2008 May 02
+*os_win32.txt*  For Vim version 7.3a.  Last change: 2008 May 02
 
 
 		  VIM REFERENCE MANUAL    by George Reilly