Index: branches/version-2_5-dev/data/class/helper/SC_Helper_Mobile.php
===================================================================
--- branches/version-2_5-dev/data/class/helper/SC_Helper_Mobile.php	(revision 19987)
+++ branches/version-2_5-dev/data/class/helper/SC_Helper_Mobile.php	(revision 19998)
@@ -43,5 +43,5 @@
     function lfMobileCheckCompatibility() {
         if (!SC_MobileUserAgent::isSupported()) {
-            header('Location: ' . ROOT_URLPATH . 'unsupported/' . DIR_INDEX_URL);
+            header('Location: ' . ROOT_URLPATH . 'unsupported/' . DIR_INDEX_PATH);
             exit;
         }
Index: branches/version-2_5-dev/data/class/util/SC_Utils.php
===================================================================
--- branches/version-2_5-dev/data/class/util/SC_Utils.php	(revision 19986)
+++ branches/version-2_5-dev/data/class/util/SC_Utils.php	(revision 19998)
@@ -86,7 +86,7 @@
             }
         }
-        $path = HTML_REALDIR . "install/index.php";
+        $path = HTML_REALDIR . 'install/' . DIR_INDEX_FILE;
         if(file_exists($path)) {
-            SC_Utils::sfErrorHeader(">> /install/index.phpは、インストール完了後にファイルを削除してください。");
+            SC_Utils::sfErrorHeader('>> /install/' . DIR_INDEX_FILE . ' は、インストール完了後にファイルを削除してください。');
         }
     }
@@ -104,5 +104,5 @@
      */
     function searchInstallerPath($path) {
-        $installer = 'install/index.php';
+        $installer = 'install/' . DIR_INDEX_PATH;
 
         if (SC_Utils::sfIsHTTPS()) {
Index: branches/version-2_5-dev/data/class/pages/forgot/LC_Page_Forgot.php
===================================================================
--- branches/version-2_5-dev/data/class/pages/forgot/LC_Page_Forgot.php	(revision 19995)
+++ branches/version-2_5-dev/data/class/pages/forgot/LC_Page_Forgot.php	(revision 19998)
@@ -302,5 +302,5 @@
         // 空メール用のトークンを作成。
         if (MOBILE_USE_KARA_MAIL) {
-            $token = $objMobile->gfPrepareKaraMail('forgot/' . DIR_INDEX_URL);
+            $token = $objMobile->gfPrepareKaraMail('forgot/' . DIR_INDEX_PATH);
             if ($token !== false) {
                 $objPage->tpl_kara_mail_to = MOBILE_KARA_MAIL_ADDRESS_USER . MOBILE_KARA_MAIL_ADDRESS_DELIMITER . 'forgot_' . $token . '@' . MOBILE_KARA_MAIL_ADDRESS_DOMAIN;
Index: branches/version-2_5-dev/data/class/pages/LC_Page_Sitemap.php
===================================================================
--- branches/version-2_5-dev/data/class/pages/LC_Page_Sitemap.php	(revision 19972)
+++ branches/version-2_5-dev/data/class/pages/LC_Page_Sitemap.php	(revision 19998)
@@ -77,5 +77,5 @@
         $this->staticURL = array();
         
-        $this->staticURL[] = HTTP_URL . 'rss/' . DIR_INDEX_URL;
+        $this->staticURL[] = HTTP_URL . 'rss/' . DIR_INDEX_PATH;
         if (USE_MOBILE !== false) {
             $this->staticURL[] = MOBILE_HTTP_URL;
@@ -311,5 +311,5 @@
                 $page['url'] = HTTP_URL . $page['url'];
             }
-            $page['url'] = preg_replace('|/' . preg_quote(DIR_INDEX_FILE) . '$|', '/' . DIR_INDEX_URL, $page['url']);
+            $page['url'] = preg_replace('|/' . preg_quote(DIR_INDEX_FILE) . '$|', '/' . DIR_INDEX_PATH, $page['url']);
         }
         unset($page);
Index: branches/version-2_5-dev/data/class/pages/mypage/LC_Page_Mypage_LoginCheck.php
===================================================================
--- branches/version-2_5-dev/data/class/pages/mypage/LC_Page_Mypage_LoginCheck.php	(revision 19959)
+++ branches/version-2_5-dev/data/class/pages/mypage/LC_Page_Mypage_LoginCheck.php	(revision 19998)
@@ -143,5 +143,5 @@
                 }
                 
-                SC_Response_Ex::sendRedirect(DIR_INDEX_URL);
+                SC_Response_Ex::sendRedirect(DIR_INDEX_PATH);
                 exit;
             }
Index: branches/version-2_5-dev/data/class/pages/mypage/LC_Page_Mypage_Login.php
===================================================================
--- branches/version-2_5-dev/data/class/pages/mypage/LC_Page_Mypage_Login.php	(revision 19959)
+++ branches/version-2_5-dev/data/class/pages/mypage/LC_Page_Mypage_Login.php	(revision 19998)
@@ -72,5 +72,5 @@
         // ログイン判定
         if($objCustomer->isLoginSuccess(true)) {
-            SC_Response_Ex::sendRedirect(DIR_INDEX_URL);
+            SC_Response_Ex::sendRedirect(DIR_INDEX_PATH);
             exit;
         } else {
Index: branches/version-2_5-dev/data/class/pages/mypage/LC_Page_Mypage.php
===================================================================
--- branches/version-2_5-dev/data/class/pages/mypage/LC_Page_Mypage.php	(revision 19959)
+++ branches/version-2_5-dev/data/class/pages/mypage/LC_Page_Mypage.php	(revision 19998)
@@ -116,5 +116,5 @@
             // next
             if ($pageNo + HISTORY_NUM < $linemax) {
-                $next = "<a href='index.php?pageno=" . ($pageNo + HISTORY_NUM) . "'>次へ→</a>";
+                $next = "<a href='?pageno=" . ($pageNo + HISTORY_NUM) . "'>次へ→</a>";
             } else {
                 $next = "";
@@ -123,9 +123,9 @@
             // previous
             if ($pageNo - HISTORY_NUM > 0) {
-                $previous = "<a href='index.php?pageno=" . ($pageNo - HISTORY_NUM) . "'>←前へ</a>";
+                $previous = "<a href='?pageno=" . ($pageNo - HISTORY_NUM) . "'>←前へ</a>";
             } elseif ($pageNo == 0) {
                 $previous = "";
             } else {
-                $previous = "<a href='index.php?pageno=0'>←前へ</a>";
+                $previous = "<a href='?pageno=0'>←前へ</a>";
             }
 
Index: branches/version-2_5-dev/data/class/pages/admin/design/LC_Page_Admin_Design.php
===================================================================
--- branches/version-2_5-dev/data/class/pages/admin/design/LC_Page_Admin_Design.php	(revision 19879)
+++ branches/version-2_5-dev/data/class/pages/admin/design/LC_Page_Admin_Design.php	(revision 19998)
@@ -210,5 +210,5 @@
                 $_SESSION['preview'] = "ON";
 
-                SC_Response_Ex::sendRedirectFromUrlPath('preview/' . DIR_INDEX_URL, array("filename" => $arrPageData[0]["filename"]));
+                SC_Response_Ex::sendRedirectFromUrlPath('preview/' . DIR_INDEX_PATH, array("filename" => $arrPageData[0]["filename"]));
                 exit;
 
Index: branches/version-2_5-dev/data/class/pages/admin/design/LC_Page_Admin_Design_MainEdit.php
===================================================================
--- branches/version-2_5-dev/data/class/pages/admin/design/LC_Page_Admin_Design_MainEdit.php	(revision 19982)
+++ branches/version-2_5-dev/data/class/pages/admin/design/LC_Page_Admin_Design_MainEdit.php	(revision 19998)
@@ -215,5 +215,5 @@
         }
         $_SESSION['preview'] = "ON";
-        SC_Response_Ex::sendRedirectFromUrlPath('preview/' . DIR_INDEX_URL, array("filename" => $arrPageData[0]["filename"]));
+        SC_Response_Ex::sendRedirectFromUrlPath('preview/' . DIR_INDEX_PATH, array("filename" => $arrPageData[0]["filename"]));
     }
 
Index: branches/version-2_5-dev/data/class/pages/admin/LC_Page_Admin_Logout.php
===================================================================
--- branches/version-2_5-dev/data/class/pages/admin/LC_Page_Admin_Logout.php	(revision 19908)
+++ branches/version-2_5-dev/data/class/pages/admin/LC_Page_Admin_Logout.php	(revision 19998)
@@ -55,5 +55,5 @@
         $objSess->logout();
 
-        SC_Response_Ex::sendRedirectFromUrlPath(ADMIN_DIR . DIR_INDEX_URL);
+        SC_Response_Ex::sendRedirectFromUrlPath(ADMIN_DIR . DIR_INDEX_PATH);
     }
 
Index: branches/version-2_5-dev/data/class/SC_Initial.php
===================================================================
--- branches/version-2_5-dev/data/class/SC_Initial.php	(revision 19987)
+++ branches/version-2_5-dev/data/class/SC_Initial.php	(revision 19998)
@@ -159,5 +159,5 @@
 
     /**
-     * 定数 DIR_INDEX_URL を設定する.
+     * 定数 DIR_INDEX_PATH を設定する.
      *
      * @access protected
@@ -171,11 +171,16 @@
         }
 
+        $useFilenameDirIndex = is_bool(USE_FILENAME_DIR_INDEX)
+            ? USE_FILENAME_DIR_INDEX
+            : (empty($_SERVER['SERVER_SOFTWARE']) ? false : substr($_SERVER['SERVER_SOFTWARE'], 0, 13) == 'Microsoft-IIS')
+        ;
+
         // DIR_INDEX_FILE にアクセスする時の URL のファイル名部を定義する
-        if (USE_FILENAME_DIR_INDEX === true) {
+        if ($useFilenameDirIndex === true) {
             // ファイル名を使用する
-            define('DIR_INDEX_URL', DIR_INDEX_FILE);
+            define('DIR_INDEX_PATH', DIR_INDEX_FILE);
         } else {
             // ファイル名を使用しない
-            define('DIR_INDEX_URL', '');
+            define('DIR_INDEX_PATH', '');
         }
     }