Multiple reminders for calendar appointments

In Zimbra 7, I was able to configure my calendar so it sent me multiple reminders for each appointment I received. In Zimbra 8, that does not seem to be possible. The reminder time can be set only by the organizer of the apppointment, and he can choose only a single reminder.

How can I set up Zimbra 8 so I get multiple reminders again, at times which *I* can configure, instead of only one that was set by the organizer?

Thanks and best regards,
Alex