Create ics in another calendar (internal server error)

[Zorg]

Hi

Let me explain

I want my admin to write event in default calendar of my user

For example myadmin at my.domain.com need to create event in 
user/myuser1/#calendars/Default

put every time i this to add event (thunderbird, evolution, curl ) i 
have this in the log  "HTTP/1.1 500 Internal Server Error" (error=The 
server encountered an internal error.)

What am i missing ?

Here is the mailbox i have and acl

user/myuser1/#calendars/Attachments at my.domain.com (\HasNoChildren)
user/myuser1/#calendars/Default at my.domain.com (\HasNoChildren)
user/myuser1/#calendars/Inbox at my.domain.com (\HasNoChildren)
user/myuser1/#calendars/Outbox at my.domain.com (\HasNoChildren)
user/myuser1/#calendars at my.domain.com (\HasNoChildren)
user/myuser1/#notifications at my.domain.com (\HasNoChildren)
user/myuser1 at my.domain.com (\HasNoChildren)




user/myuser1 at my.domain.com:
   myadmin at my.domain.com lrswipkxtecdan
   myuser1 at my.domain.com lrswipkxtecdan
user/myuser1/#calendars at my.domain.com:
   anyone 9
   myadmin at my.domain.com lrswipkxtecdan9
   myuser1 at my.domain.com lrswipkxtecdan9
user/myuser1/#calendars/Attachments at my.domain.com:
   myuser1 at my.domain.com lrswipkxtecdan
   myadmin at my.domain.com lrswipkxtecdan9
   anyone r
user/myuser1/#calendars/Default at my.domain.com:
   anyone 9
   myadmin at my.domain.com lrswipkxtecdan9
   myuser1 at my.domain.com lrswipkxtecdan9
user/myuser1/#calendars/Inbox at my.domain.com:
   myadmin at my.domain.com lrswipkxtecdan9
   anyone 789
   myuser1 at my.domain.com lrswipkxtecdan789
user/myuser1/#calendars/Outbox at my.domain.com:
   myadmin at my.domain.com lrswipkxtecdan9
   anyone 9
   myuser1 at my.domain.com lrswipkxtecdan789
user/myuser1/#notifications at my.domain.com:
   myuser1 at my.domain.com lrswipkxtecdan
   myadmin at my.domain.com lrswipkxtecdan9


Thanks