I am working on a Zimbra integration project, where secretaries will have to handle appointments for other users. Thus, they have many calendars for each user in folders view, and it become hard to have a clean view.

I am wondering : is there a way to organize calendars as a tree, such as mail folders ?

I tried to create calendars subfolder with zmmailbox commandline utility. It seems to display quite correctly in folders view, but child folders can't be selected when creating new appointments.
And calendars list is empty when modifying an appointment.

Is there a way to get this working ?
Is it planned in further enhancement to allow organizing calendar folders ?

Thanks for any response.