[TYPO3-dev] Scheduler: Task disables itself automatically

[roberto blanko]

Hello TYPO3 community,

I've developed my own task for the scheduler which is supposed to run every
5 minutes.

I'm using the following settings:

Type: Recurring
Start: Current time
End: Blank
Frequency: 300
Allow parallel execution: No

If I execute the task manually using the scheduler's backend module,
everything works as expected. The task is executed and the next execution
time is set to time()+300.

BUT: If the task is executed via Cron, its being disabled the first time its
supposed to run. It's being disabled even before the actual run() method in
the task class is called. From now on the task isn't executed anymore -
cause its disabled of course.

What could be the cause for this? Please help me out! I'm desperate!

Looking forward for replies.