[Dovecot] Problem: delivery with mode 600 into shared folder

Hi, I have a problem, delivery called from /etc/aliases file by pipe delivers with mode 0600. I need system users with shared mail folders (Maildir format). When I changed alias to pipe to shell wrapper with mode 002 set in it, nothing changed. MTA is sendmail, OS Solaris, and dovecot version 1.1.1. Can somebody help?

Here are dovecot settings:

/opt/dovecot11/sbin/dovecot -n # 1.1.1: /opt/dovecot11/etc/dovecot.conf base_dir: /var/run/dovecot/ log_path: /var/log/dovecot.log login_dir: /var/run/dovecot//login login_executable: /opt/dovecot11/libexec/amd64/dovecot/imap-login max_mail_processes: 128 mail_location: maildir:/home/vmail/listuser/Maildir:CONTROL=/home/vmail/%u/Maildir/control:INDEX=/home/vmail/%u/Maildir/index mail_debug: yes auth default: verbose: yes debug: yes debug_passwords: yes passdb: driver: pam args: imap userdb: driver: passwd socket: type: listen master: path: /var/run/dovecot/auth-master mode: 432 user: daemon group: other plugin: sieve: /opt/dovecot11/sieve-scripts/folders.sieve

And this is the alias to pipe:

grep deliver /etc/aliases listuser@domain.com: "|/opt/dovecot11/libexec/dovecot/deliver -d listuser"

Sergey Ivanov.