diff --git a/ChangeLog b/ChangeLog
index dfc458fc4..fd664d3cd 100755
--- a/ChangeLog
+++ b/ChangeLog
@@ -9,6 +9,7 @@ $Source$
     * lang/sort_lang.sh: Fix status output bug '\n'
     * db_details_importdocsql.php3: Move hardcoded strings to language files 
     * lang/*.php3: Add new strings for docSQL importer
+    * libraries/sqlvalidator.*.php3: Finish fixing bug #644709
 
 2003-01-15 Alexander M. Turek  <rabus@users.sourceforge.net>
     * lang/lithuanian-*.inc.php3: Updates, thanks to Vilius Zigmantas (viliusz).
diff --git a/libraries/sqlvalidator.class.php3 b/libraries/sqlvalidator.class.php3
index 50659afc1..f61642ce5 100644
--- a/libraries/sqlvalidator.class.php3
+++ b/libraries/sqlvalidator.class.php3
@@ -402,6 +402,12 @@ if (!defined('PMA_SQL_VALIDATOR_CLASS_INCLUDED')) {
 
             } // end of the "validationString()" function
         } // end class PMA_SQLValidator
+
+        //add an extra check to ensure that the class was defined without errors
+        if (!class_exists('PMA_SQLValidator')) {
+            $GLOBALS['sqlvalidator_error'] = TRUE;
+        }
+
     } // end else
 
 }  // $__PMA_SQL_VALIDATOR_CLASS__
diff --git a/libraries/sqlvalidator.lib.php3 b/libraries/sqlvalidator.lib.php3
index 9fd3c243a..9dbcc29b3 100644
--- a/libraries/sqlvalidator.lib.php3
+++ b/libraries/sqlvalidator.lib.php3
@@ -64,8 +64,10 @@ if (!defined('PMA_SQL_VALIDATOR_INCLUDED')) {
         $str = '';
 
         if ($cfg['SQLValidator']['use']) {
-            if (!(isset($GLOBALS['sqlvalidator_error'])
-                && !$GLOBALS['sqlvalidator_error'])) {
+            if (isset($GLOBALS['sqlvalidator_error'])
+                && $GLOBALS['sqlvalidator_error']) {
+                $str = sprintf($GLOBALS['strValidatorError'], '<a href="./Documentation.html#faqsqlvalidator" target="documentation">', '</a>');
+            } else {
                 // create new class instance
                 $srv = new PMA_SQLValidator();
 
@@ -87,10 +89,6 @@ if (!defined('PMA_SQL_VALIDATOR_INCLUDED')) {
 
                 // Do service validation
                 $str = $srv->validationString($sql);
-
-            } else {
-                $str = sprintf($GLOBALS['strValidatorError'], '<a href="./Documentation.html#faqsqlvalidator" target="documentation">', '</a>');
-
             }
 
         } // end if