Fixed #3835 Delete MailBackup not working - Log shows a warning about SQL I...

Till Brehm

2016-04-20 86853d4d0fd66c277746e9e0cf07fbecbfbbc362

1
ALTER TABLE  `sys_session` CHANGE  `session_id`  `session_id` VARCHAR( 64 ) CHARACTER SET latin1 COLLATE latin1_swedish_ci NOT NULL;