Outbound setting reverts in non-production sites on executing sched job

If a site is changed to development mode in newly added setting - http://dmaster.demo.civicrm.org/civicrm/admin/setting/debug?reset=1, outbound mail gets disabled in http://dmaster.demo.civicrm.org/civicrm/admin/setting/smtp?reset=1. It then gets restored to mail() or its original value when one of the schedule job is executed using "runInNonProductionEnvironment=TRUE" parameter.

To replicate -

1/ Change site to development mode in http://dmaster.demo.civicrm.org/civicrm/admin/setting/debug?reset=1
2/ Note that outbound mail is disabled on http://dmaster.demo.civicrm.org/civicrm/admin/setting/smtp?reset=1
3/ Enable and execute one of the schedule job eg "rebuild smart group cache" using runInNonProductionEnvironment=TRUE parameter.
4/ Check the outbound mail setting. It gets reverted to mail().

This is a major problem on dev sites as user thinks the outbound is disabled, but the site could result in sending emails to the contacts.