diff --git a/ChangeLog b/ChangeLog
index 4deb6b360..71a102ee9 100755
--- a/ChangeLog
+++ b/ChangeLog
@@ -10,6 +10,7 @@ $Source$
       libraries/display_tbl.lib.php: Support for exporting selected rows (RFE
       #927554) [still missing images/button_export.png, waiting for somebody
       to make it :-)].
+    * libraries/auth/cookie.auth.lib.php: Fix possible undefined variable use.
 
 2004-04-15 Olivier Mueller <om@omnis.ch>
     * left.php: RFE #859208, Logout button in left frame
diff --git a/libraries/auth/cookie.auth.lib.php b/libraries/auth/cookie.auth.lib.php
index caeb9051b..9a7a32c02 100644
--- a/libraries/auth/cookie.auth.lib.php
+++ b/libraries/auth/cookie.auth.lib.php
@@ -154,7 +154,7 @@ function PMA_auth()
         else if (!empty($_COOKIE) && isset($_COOKIE['pma_cookie_username'])) {
             $default_user = $_COOKIE['pma_cookie_username'];
         }
-        $decrypted_user = PMA_blowfish_decrypt($default_user, $GLOBALS['cfg']['blowfish_secret']);
+        $decrypted_user = isset($default_user) ? PMA_blowfish_decrypt($default_user, $GLOBALS['cfg']['blowfish_secret']) : '';
         $pos = strrpos($decrypted_user, ':');
         $default_user = substr($decrypted_user, 0, $pos);