--- a.vim.orig	2004-09-16 15:13:29 +0600
+++ a.vim	2004-09-17 15:57:54 +0600
@@ -16,6 +16,10 @@
 "       b) Priorities for search paths
 "       c) <leader>A on a #include line should go to that header
 
+if !exists("use_alternate_plugin")
+    finish
+endif
+
 " Do not load a.vim if is has already been loaded.
 if exists("loaded_alternateFile")
     finish