[Dovecot] Umask of Homedir

[Francisco Wagner C. Freire]

Hello,

I following the instrucions of:
http://wiki2.dovecot.org/SharedMailboxes/Permissions

When the user receive the first mail, dovecot create the directory structure
always using mode 0700, if i change the permission of the user maildir all
new mails arrived get the correct umask:
dovecot: lmtp(24960, *): Debug: Namespace INBOX.: Using permissions from
.../maildir: mode=0770

The problem is: I need to all accounts have the permission 0770. Tried to
use the option: mail_access_groups but doesn't work at all when the first
creation of the user path.

"For example a simple way to set up shared mailbox access for all system
users is to make all mail dirs/files 0770/0660 mode and owned by group
"sharedmail" and then set mail_access_groups=sharedmail. Using more fine
grained groups of course leaks less mail data in case there's a security
hole in Dovecot"

Is a bug?

My dovecot version:

doveconf  -n
# 2.0.12 (811a6d173bb2): /etc/dovecot/dovecot.conf
# OS: Linux 2.6.32-5-amd64 x86_64 Debian 6.0.1

Access groups:
mail_access_groups = _sysadms

Thanks and sorry for bad english.