diff --git a/ChangeLog b/ChangeLog
index 988bdc4f8..de0346f68 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -5,6 +5,9 @@ phpMyAdmin - ChangeLog
 $Id$
 $HeadURL$
 
+2007-02-14 Marc Delisle  <lem9@users.sourceforge.net>
+    * add a warning on main page if mcrypt can't be loaded (bug 1658160)
+
 2007-02-12 Sebastian Mendel <cybot_tm@users.sourceforge.net>
     * libraries/database_interface.lib.php: bug #1616486 server_databases does
       not show all databases
diff --git a/libraries/auth/cookie.auth.lib.php b/libraries/auth/cookie.auth.lib.php
index 881a8f945..88788ee77 100644
--- a/libraries/auth/cookie.auth.lib.php
+++ b/libraries/auth/cookie.auth.lib.php
@@ -22,6 +22,8 @@ if (function_exists('mcrypt_encrypt') || PMA_dl('mcrypt')) {
     require_once './libraries/mcrypt.lib.php';
 } else {
     require_once './libraries/blowfish.php';
+    // for main.php:
+    define('PMA_WARN_FOR_MCRYPT',1);
 }
 
 
diff --git a/main.php b/main.php
index bd2f6c880..bb4fb14ad 100644
--- a/main.php
+++ b/main.php
@@ -394,6 +394,10 @@ if (defined('PMA_MYSQL_INT_VERSION') && PMA_MYSQL_INT_VERSION < 32332) {
     echo '<div class="warning">' . sprintf($strUpgrade, 'MySQL', '3.23.32') . '</div>' . "\n";
 }
 
+if (defined('PMA_WARN_FOR_MCRYPT')) {
+    echo '<div class="warning">' . PMA_sanitize(sprintf($strCantLoad, 'mcrypt')) . '</div>' . "\n";
+}
+
 /**
  * prints list item for main page
  *