The JITL Job sos.scheduler.managed.JobSchedulerManagedMailJob has always the exit code 0

Current Situation

If the JITL Job sos.scheduler.managed.JobSchedulerManagedMailJob has an error than it logs it only as warning and has the exit code 0.

2016-04-15 12:08:45.691+0200 [WARN]   mail server is unavailable, mail for recipient [xxx@xxx] is queued in local directory [C:/ProgramData/sos-berlin.com/jobscheduler/scheduler.1.10/mail]:AuthenticationFailedException while connecting to mail.gmx.net:587 xxx/******** -->535-Authentication credentials invalid
2016-04-15 12:08:45.691+0200 [WARN]   535 Insufficient security or privacy level.

The mail will be store in the mail queue directory. It is intended that the job dequeueMail will be able to send the mail later.

Desired Behavior

If the job has an error then it should log it as an error and have an exit code unequal 0.
When an error occurred while sending an email not the mail class should be responsible for the error handling but the job chain should have a setback or some other error handling steps. It It should be possible to enable the error handling with the class by setting the parameter queue_mail_on_error=true|false, default=true