[Dovecot] Symlink shared mailboxes and system_user extra field

Hello,

I'm trying to set up, as explained in the wiki, shared mailboxes with symlink. I'm running dovecot-1.1.8 with LDAP pass/userdb. The Maildir layout goes like this :

/courriel/boites/foobar : Maildir of user foobar (nfs) /courriel/meta/foobar : control files of user foobar (nfs) /var/dovecot/indexes : indexes (locally stored)

I created :

/courriel/boites/doveshared/.box/ : the Maildir I want to share /courriel/boites/foobar/.box -> /courriel/boites/doveshared/.box (symlink) /courriel/boites/foobaz/.box -> /courriel/boites/doveshared/.box (symlink)

the unix and LDAP group doveshared, so /etc/group holds :

doveshared:*:<gid>:foobar,foobaz

the permissions on the real Maildir are ok for that group :

drwxrwx---  3 root  doveshared  4096 Jan 26 18:58 /courriel/boites/doveshared
drwxrwx---  5 root  doveshared  4096 Jan 26 18:58 .box (in /courriel/boites)

I made the userdb (prefetch) return the system_user extra_field (for now, I'm using an used LDAP attribute - I will create a new attribute in my schema later) :

pass_attrs = uid=user,userPassword=password,homeDirectory=userdb_home,,,uidNumber=userdb_uid,gidNumber=userdb_gid,shadowMax=userdb_system_user

and it seems to be actually returned :

Jan 27 09:34:10 munster3 dovecot: auth(default): ldap(foobar,157.99.64.42): result: uid(user)=foobar uidNumber(userdb_uid)=xxx gidNumber(userdb_gid)=xxx homeDirectory(userdb_home)=/home1/xxx/foobar userPassword(password)=<hidden> shadowMax(userdb_system_user)=380

But I can't subscribe to the mailbox :

stat(/courriel/boites/doveshared/.box/tmp) failed: Permission denied (euid=xxx egid=<primary gid>)

as a matter of fact, the egid seems to be the primary gid.

What am I missing ?

Thanks.

-- Thomas Hummel | Institut Pasteur <hummel@pasteur.fr> | Pôle informatique - systèmes et réseau