diff --git a/adm/board_copy.php b/adm/board_copy.php
index b1b0bce40..cbb479fd8 100644
--- a/adm/board_copy.php
+++ b/adm/board_copy.php
@@ -1,6 +1,6 @@
 <?
 $sub_menu = "300100";
-define('_CAPTCHA_', 1);
+define('G4_CAPTCHA', 1);
 include_once("./_common.php");
 
 auth_check($auth[$sub_menu], 'w');
diff --git a/adm/board_copy_update.php b/adm/board_copy_update.php
index d8f290d47..83666b9cf 100644
--- a/adm/board_copy_update.php
+++ b/adm/board_copy_update.php
@@ -1,6 +1,6 @@
 <?
 $sub_menu = '300100';
-define('_CAPTCHA_', 1);
+define('G4_CAPTCHA', 1);
 include_once('./_common.php');
 
 auth_check($auth[$sub_menu], 'w');
diff --git a/adm/board_form.php b/adm/board_form.php
index e0210fc69..afd02acd0 100644
--- a/adm/board_form.php
+++ b/adm/board_form.php
@@ -1,6 +1,6 @@
 <?
 $sub_menu = "300100";
-define('_EDITOR_', 1);
+define('G4_EDITOR', 1);
 include_once('./_common.php');
 
 auth_check($auth[$sub_menu], 'w');
diff --git a/bbs/board.php b/bbs/board.php
index 582aee35e..f509d8628 100644
--- a/bbs/board.php
+++ b/bbs/board.php
@@ -1,5 +1,5 @@
 <?
-define('_CAPTCHA_', 1);
+define('G4_CAPTCHA', 1);
 include_once('./_common.php');
 
 if (!$board['bo_table']) {
diff --git a/bbs/ckeditor/ckeditor.lib.php b/bbs/ckeditor/ckeditor.lib.php
index 47c828ac9..0f4908496 100644
--- a/bbs/ckeditor/ckeditor.lib.php
+++ b/bbs/ckeditor/ckeditor.lib.php
@@ -5,7 +5,7 @@ function editor_html($id, $content, $class="")
 {
     if ( (isset($GLOBALS['is_dhtml_editor']) && $GLOBALS['is_dhtml_editor']) || !isset($GLOBALS['is_dhtml_editor']) ) {
         $str  = "<textarea id=\"$id\" name=\"$id\" class=\"ckeditor $class\" rows=\"10\" style=\"width:100%;\">$content</textarea>\n";
-        //if (_EDITOR_) $str .= "<script>CKEDITOR.replace('$id',{height:'500px'});</script>\n";
+        //if (G4_EDITOR) $str .= "<script>CKEDITOR.replace('$id',{height:'500px'});</script>\n";
     } else {
         $str  = "<textarea id=\"$id\" name=\"$id\" class=\"$class\" rows=\"10\" style=\"width:100%;\">$content</textarea>\n";
     }
diff --git a/bbs/formmail.php b/bbs/formmail.php
index a60774823..a62a887fa 100644
--- a/bbs/formmail.php
+++ b/bbs/formmail.php
@@ -1,5 +1,5 @@
 <?
-define('_CAPTCHA_', 1);
+define('G4_CAPTCHA', 1);
 include_once('./_common.php');
 
 if (!$config[cf_email_use])
diff --git a/bbs/gcaptcha/get.php b/bbs/gcaptcha/get.php
index faacdcacd..e1b0e4a5e 100644
--- a/bbs/gcaptcha/get.php
+++ b/bbs/gcaptcha/get.php
@@ -1,5 +1,5 @@
 <?php
-define('_CAPTCHA_', 1);
+define('G4_CAPTCHA', 1);
 include_once("./_common.php");
 
 echo chk_captcha();
diff --git a/bbs/memo_form.php b/bbs/memo_form.php
index a790f49f6..6e5c87a70 100644
--- a/bbs/memo_form.php
+++ b/bbs/memo_form.php
@@ -1,5 +1,5 @@
 <?
-define('_CAPTCHA_', 1);
+define('G4_CAPTCHA', 1);
 include_once('./_common.php');
 
 if ($is_guest)
diff --git a/bbs/memo_form_update.php b/bbs/memo_form_update.php
index 759920eec..ce3031a18 100644
--- a/bbs/memo_form_update.php
+++ b/bbs/memo_form_update.php
@@ -1,5 +1,5 @@
 <?
-define('_CAPTCHA_', 1);
+define('G4_CAPTCHA', 1);
 include_once('./_common.php');
 
 <<<<<<< HEAD
diff --git a/bbs/password_lost.php b/bbs/password_lost.php
index 7239b6bc7..14f8241a2 100644
--- a/bbs/password_lost.php
+++ b/bbs/password_lost.php
@@ -1,5 +1,5 @@
 <?
-define('_CAPTCHA_', 1);
+define('G4_CAPTCHA', 1);
 include_once('./_common.php');
 
 if ($is_member) {
diff --git a/bbs/password_lost2.php b/bbs/password_lost2.php
index 027a5afc7..5549a8c26 100644
--- a/bbs/password_lost2.php
+++ b/bbs/password_lost2.php
@@ -1,5 +1,5 @@
 <?
-define('_CAPTCHA_', 1);
+define('G4_CAPTCHA', 1);
 include_once('./_common.php');
 include_once($g4['path'].'/lib/mailer.lib.php');
 
diff --git a/bbs/register_form.php b/bbs/register_form.php
index 980178e98..d39f05713 100644
--- a/bbs/register_form.php
+++ b/bbs/register_form.php
@@ -1,5 +1,5 @@
 <?
-define('_CAPTCHA_', 1);
+define('G4_CAPTCHA', 1);
 include_once('./_common.php');
 include_once($g4['path'].'/lib/register.lib.php');
 
diff --git a/bbs/register_form_update.php b/bbs/register_form_update.php
index 3d66d11f4..838edac33 100644
--- a/bbs/register_form_update.php
+++ b/bbs/register_form_update.php
@@ -1,5 +1,5 @@
 <?
-define('_CAPTCHA_', 1);
+define('G4_CAPTCHA', 1);
 include_once('./_common.php');
 include_once($g4['path'].'/lib/register.lib.php');
 include_once($g4['path'].'/lib/mailer.lib.php');
diff --git a/bbs/write.php b/bbs/write.php
index d9ee6b4a4..fd3921fc2 100644
--- a/bbs/write.php
+++ b/bbs/write.php
@@ -1,6 +1,6 @@
 <?
-define('_EDITOR_', 1);
-define('_CAPTCHA_', 1);
+define('G4_EDITOR', 1);
+define('G4_CAPTCHA', 1);
 include_once('./_common.php');
 
 set_session('ss_bo_table', $bo_table);
diff --git a/bbs/write_comment_update.php b/bbs/write_comment_update.php
index f68333688..e8dd3b9df 100644
--- a/bbs/write_comment_update.php
+++ b/bbs/write_comment_update.php
@@ -1,5 +1,5 @@
 <?
-define('_CAPTCHA_', true);
+define('G4_CAPTCHA', true);
 include_once('./_common.php');
 
 // 090710
diff --git a/bbs/write_update.php b/bbs/write_update.php
index 71a3e0b60..cade2ae1d 100644
--- a/bbs/write_update.php
+++ b/bbs/write_update.php
@@ -1,5 +1,5 @@
 <?
-define('_CAPTCHA_', 1);
+define('G4_CAPTCHA', 1);
 include_once('./_common.php');
 
 $g4['title'] = '게시글 저장';
diff --git a/extend/ckeditor.extend.php b/extend/ckeditor.extend.php
deleted file mode 100644
index 419dc09bf..000000000
--- a/extend/ckeditor.extend.php
+++ /dev/null
@@ -1,21 +0,0 @@
-<?
-if (!defined('_GNUBOARD_')) exit; // 개별 페이지 접근 불가
-/*
-// _EDITOR_ 의 값에 상관없이 선언 되었는지의 여부만 따짐
-// if (defined('_EDITOR_')) true;
-define('_EDITOR_', 1);
-
-if (defined('_EDITOR_')) {
-    $ckeditor = new stdClass;
-    $ckeditor->url  = $g4['url']."/extend/ckeditor";
-    $ckeditor->path = $g4['path']."/extend/ckeditor";
-    $ckeditor->data = "data/editor";
-
-    include_once($ckeditor->path."/ckeditor.lib.php");
-
-    $g4['js_code'][] = "var g4_ckeditor_path = \"{$ckeditor->path}\";";
-    $g4['js_file'][] = $ckeditor->url."/ckeditor.js";
-    $g4['js_file'][] = $ckeditor->url."/config.js";
-}
-*/
-?>
\ No newline at end of file
diff --git a/extend/g4s.extend.php b/extend/g4s.extend.php
index def09b2d2..d16641485 100644
--- a/extend/g4s.extend.php
+++ b/extend/g4s.extend.php
@@ -22,8 +22,8 @@ $g4['cache_path']     = $g4['data_path'].'/'.$g4['cache_dir'];
 $g4['captcha_dir']    = 'captcha';
 
 // g4s 기본 DHTML EDITOR
-if (!defined('_EDITOR_')) define('_EDITOR_', 0);
-if (_EDITOR_) {
+if (!defined('G4_EDITOR')) define('G4_EDITOR', 0);
+if (G4_EDITOR) {
     $g4['ckeditor_dir']  = 'ckeditor';
     $g4['ckeditor_url']  = $g4['bbs_url'].'/'.$g4['ckeditor_dir'];
     $g4['ckeditor_path'] = $g4['bbs_path'].'/'.$g4['ckeditor_dir'];
@@ -37,8 +37,8 @@ if (_EDITOR_) {
 }
 
 // g4s 기본 CAPTCHA
-if (!defined('_CAPTCHA_')) define('_CAPTCHA_', 0);
-if (_CAPTCHA_) {
+if (!defined('G4_CAPTCHA')) define('G4_CAPTCHA', 0);
+if (G4_CAPTCHA) {
     $g4['gcaptcha_dir']   = 'gcaptcha';
     $g4['gcaptcha_url']   = $g4['bbs_url'].'/'.$g4['gcaptcha_dir'];
     $g4['gcaptcha_path']  = $g4['bbs_path'].'/'.$g4['gcaptcha_dir'];
diff --git a/extend/gcaptcha.extend.php b/extend/gcaptcha.extend.php
deleted file mode 100644
index 129ec511a..000000000
--- a/extend/gcaptcha.extend.php
+++ /dev/null
@@ -1,22 +0,0 @@
-<?
-if (!defined('_GNUBOARD_')) exit; // 개별 페이지 접근 불가
-
-/*
-// _CAPTCHA_ 의 값에 상관없이 선언 되었는지의 여부만 따짐
-// if (defined('_CAPTCHA_')) true;
-define('_CAPTCHA_', 1);
-
-if (defined('_CAPTCHA_')) {
-    $gcaptcha = new stdClass;
-    $gcaptcha->url   = $g4['url']."/extend/gcaptcha";
-    $gcaptcha->path  = $g4['path']."/extend/gcaptcha";
-    $gcaptcha->fonts = $gcaptcha->path."/fonts";
-    $gcaptcha->wavs  = $gcaptcha->path."/wavs";
-
-    include_once($gcaptcha->path."/gcaptcha.lib.php");
-
-    $g4['js_code'][] = "var g4_gcaptcha_path = \"{$gcaptcha->path}\";";
-    $g4['js_file'][] = $gcaptcha->url."/gcaptcha.js";
-}
-*/
-?>
\ No newline at end of file