Redmine

I'm using Redmine 1.3.1 stable. Now, I want to customize a plugin which doing the same task with reminders.

There some plugins similar to reminders are: send_whining or redmine_reminder. But all of them just send email reminder once time, based on the parameter: days=X

I want to send email reminder three times from the created_on and due_date. It means that: each issue have a created_on and due_date:

range = (due_date - created_on)/3

The 1st email: created_on + range
The 2nd email: created_on + range * 2
The 3rd email: on the due_date

Thus, I do it by call the 'end_reminders' task three time. But I don't know how to create a task invoke another task inside it.

Is there any plugin can do that?

Thanks you for all your help!