Update runtime files.
diff --git a/runtime/ftplugin/man.vim b/runtime/ftplugin/man.vim
index c7fc3bb..cfcabc3 100644
--- a/runtime/ftplugin/man.vim
+++ b/runtime/ftplugin/man.vim
@@ -1,7 +1,7 @@
 " Vim filetype plugin file
 " Language:	man
 " Maintainer:	SungHyun Nam <goweol@gmail.com>
-" Last Change: 	2017 Jan 18
+" Last Change: 	2017 Nov 11
 
 " To make the ":Man" command available before editing a manual page, source
 " this script from your startup vimrc file.
@@ -15,12 +15,6 @@
   endif
   let b:did_ftplugin = 1
 
-  " Ensure Vim is not recursively invoked (man-db does this)
-  " when doing ctrl-[ on a man page reference.
-  if exists("$MANPAGER")
-    let $MANPAGER = ""
-  endif
-
   " allow dot and dash in manual page name.
   setlocal iskeyword+=\.,-
 
@@ -176,7 +170,11 @@
     let $MANWIDTH = winwidth(0)
     let unsetwidth = 1
   endif
-  silent exec "r !man ".s:GetCmdArg(sect, page)." | col -b"
+
+  " Ensure Vim is not recursively invoked (man-db does this) when doing ctrl-[
+  " on a man page reference by unsetting MANPAGER.
+  silent exec "r !env -u MANPAGER man ".s:GetCmdArg(sect, page)." | col -b"
+
   if unsetwidth
     let $MANWIDTH = ''
   endif