diff --git a/runtime/spell/cleanadd.vim b/runtime/spell/cleanadd.vim
new file mode 100644
index 0000000..14eb83a
--- /dev/null
+++ b/runtime/spell/cleanadd.vim
@@ -0,0 +1,22 @@
+" Vim script to clean the ll.xxxxx.add files of commented out entries
+" Author:	Antonio Colombo, Bram Moolenaar
+" Last Update:	2006 Jan 19
+
+" Time in seconds after last time an ll.xxxxx.add file was updated
+" Default is one hour.
+if !exists("g:spell_clean_limit")
+  let g:spell_clean_limit = 60 * 60
+endif
+
+" Loop over all the runtime/spell/*.add files.
+for s:fname in split(globpath(&rtp, "spell/*.add"), "\n")
+  if filewritable(s:fname) && localtime() - getftime(s:fname) > g:spell_clean_limit
+    silent exe "split " . escape(s:fname, ' \')
+    echo "Processing" s:fname
+    silent! g/^#/d
+    silent update
+    close
+  endif
+endfor
+
+echo "Done"