updated for version 7.0d04
diff --git a/runtime/ftplugin/ruby.vim b/runtime/ftplugin/ruby.vim
index 4c8db85..8ce7f12 100644
--- a/runtime/ftplugin/ruby.vim
+++ b/runtime/ftplugin/ruby.vim
@@ -51,6 +51,7 @@
 setlocal include=^\\s*\\<\\(load\\\|\w*require\\)\\>
 setlocal includeexpr=substitute(substitute(v:fname,'::','/','g'),'$','.rb','')
 setlocal suffixesadd=.rb
+setlocal omnifunc=rubycomplete#Complete 
 
 " TODO:
 "setlocal define=^\\s*def