diff --git a/after5.rb b/after5.rb
index 2ea9e7e..ec4e794 100755
--- a/after5.rb
+++ b/after5.rb
@@ -4,7 +4,7 @@
 # Associative Scheduling Table - after5
 # (C)2003, 2004, 2006, 2008, 2012-2014 by HIROSE Yuuji [yuuji<at>gentei.org]
 # $Id: after5.rb,v 1.20 2012/12/03 15:54:20 yuuji Exp $
-# Last modified Sat Aug 30 16:49:33 2014 on firestorm
+# Last modified Sat Apr 29 09:24:49 2017 on firestorm
 # See http://www.gentei.org/~yuuji/software/after5/
 # ���Υ�����ץȤ�EUC����¸���Ƥ���������
 $hgid = <<_HGID_.split[1..-2].join(" ")
@@ -3435,7 +3435,9 @@
       if @params[key]
         #
         # Check the group is invitation-only mode.
-        if !removep && !memberp && !@sc.isadmin(user, grp)
+        if !removep && !memberp \
+          && @sc.getgroupattr(grp, 'inviteonly') \
+          && !@sc.isadmin(user, grp)
           @O.print @H.elementln("p") {
             sprintf(msg('invite-error'), grp) + "<br>\n" + \
             @sc.admins(grp).join(", ")
@@ -3449,7 +3451,7 @@
           next
         end
         #
-        # OK to join/retire 
+        # OK to join/retire
 	if (!removep) ^ memberp
 	  @sc.addgroup(grp, [user], removep)
 	  @O.print @H.elementln("p"){