[Dovecot] All messages in double in a virtual mailbox.

[François-Xavier Payet]

Hello,
I've got some virtual maiboxes that are configured as follows :
!RealMail.Sent
RealMail.Sent
  all

In all those mailboxes, all the messages appears in double. I don't 
think it's the expected behaviour, but I perhaps missed something.

Here's my dovecot -n :

# 1.2.15: /etc/dovecot/dovecot.conf
# OS: Linux 2.6.32-bpo.5-amd64 x86_64 Debian 5.0.7
log_timestamp: %Y-%m-%d %H:%M:%S
protocols: imaps managesieve
login_dir: /var/run/dovecot/login
login_executable(default): /usr/lib/dovecot/imap-login
login_executable(imap): /usr/lib/dovecot/imap-login
login_executable(managesieve): /usr/lib/dovecot/managesieve-login
mail_privileged_group: mail
mbox_write_locks: fcntl dotlock
mail_executable(default): /usr/lib/dovecot/imap
mail_executable(imap): /usr/lib/dovecot/imap
mail_executable(managesieve): /usr/lib/dovecot/managesieve
mail_plugins(default): virtual
mail_plugins(imap): virtual
mail_plugins(managesieve):
mail_plugin_dir(default): /usr/lib/dovecot/modules/imap
mail_plugin_dir(imap): /usr/lib/dovecot/modules/imap
mail_plugin_dir(managesieve): /usr/lib/dovecot/modules/managesieve
namespace:
  type: private
  separator: .
  location: virtual:/var/vmail/%d/%n/Maildir/virtual
  inbox: yes
  list: yes
  subscriptions: yes
namespace:
  type: private
  separator: .
  prefix: RealMail.
  location: maildir:/var/vmail/%d/%n/Maildir
  hidden: yes
  list: no
  subscriptions: yes
lda:
  log_path: /var/vmail/dovecot-deliver.log
  auth_socket_path: /var/run/dovecot/auth-master
  postmaster_address: f...@da-foux-server.tfdn.org
  mail_plugins: sieve virtual
auth default:
  mechanisms: plain login
  passdb:
    driver: sql
    args: /etc/dovecot/dovecot-sql.conf
  userdb:
    driver: passwd
  userdb:
    driver: static
    args: uid=5000 gid=5000 home=/var/vmail/%d/%n allow_all_users=yes
  socket:
    type: listen
    client:
      path: /var/spool/postfix/private/auth
      mode: 432
      user: postfix
      group: postfix
    master:
      path: /var/run/dovecot/auth-master
      mode: 384
      user: vmail
plugin:
  sieve: /var/vmail/%d/%n/sieve
  sieve_dir: /var/vmail/%d/%n/.sieve

Thanks for your help
François-Xavier Payet