diff --git a/ChangeLog b/ChangeLog
index 0041682ff..16c36aebc 100755
--- a/ChangeLog
+++ b/ChangeLog
@@ -5,6 +5,10 @@ phpMyAdmin - Changelog
 $Id$
 $Source$
 
+2004-09-03 Michal Čihař  <michal@cihar.com>
+    * libraries/string.lib.php: Encoding tis-620 is not multibyte (bug
+      #1013787).
+
 2004-09-01 Marc Delisle  <lem9@users.sourceforge.net>
     * libraries/auth/cookie.auth.lib.php: bug 939531: when people upgrade
       phpMyAdmin on the same directory, the previous cookie pma_cookie_username
diff --git a/libraries/string.lib.php b/libraries/string.lib.php
index 5bb427543..a31860e56 100644
--- a/libraries/string.lib.php
+++ b/libraries/string.lib.php
@@ -14,7 +14,12 @@
  * The SQL Parser code relies heavily on these functions.
  */
  
-$GLOBALS['PMA_allow_mbstr'] = @function_exists('mb_strlen') && substr($GLOBALS['charset'], 0, 8) != 'windows-';
+ /* windows-* and tis-620 are not supported and are not multibyte, so there is
+  * no need to handle them. */
+$GLOBALS['PMA_allow_mbstr'] = @function_exists('mb_strlen') 
+    && substr($GLOBALS['charset'], 0, 8) != 'windows-' 
+    && $GLOBALS['charset'] != 'tis-620';
+
 if ($GLOBALS['PMA_allow_mbstr']) {
     // the hebrew lang file uses iso-8859-8-i, encoded RTL,
     // but mb_internal_encoding only supports iso-8859-8