diff --git a/lib/db/upgrade.php b/lib/db/upgrade.php
index b01b4513593..b4788b4ddfb 100644
--- a/lib/db/upgrade.php
+++ b/lib/db/upgrade.php
@@ -1813,16 +1813,16 @@ WHERE gradeitemid IS NOT NULL AND grademax IS NOT NULL");
     }
 
     if ($result && $oldversion < 2009050607) {
-
+//TODO: remove, this field does not exist yet!
     /// Changing precision of field defaultregion on table block_instances to (16)
-        $table = new xmldb_table('block_instances');
+/*        $table = new xmldb_table('block_instances');
         $field = new xmldb_field('defaultregion', XMLDB_TYPE_CHAR, '16', null, XMLDB_NOTNULL, null, null, 'subpagepattern');
 
     /// Launch change of precision for field defaultregion
         $dbman->change_field_precision($table, $field);
 
     /// Main savepoint reached
-        upgrade_main_savepoint($result, 2009050607);
+        upgrade_main_savepoint($result, 2009050607);*/
     }
 
     if ($result && $oldversion < 2009050608) {