Got it ! It was the altnamespace option in /etc/imapd.conf that was set to no (debian's default).
# Alternate namespace # If enabled, activate the alternate namespace as documented in # /usr/share/doc/cyrus-doc-2.2/html/altnamespace.html, where an user's # subfolders are in the same level as the INBOX # See also userprefix and sharedprefix on imapd.conf(5) altnamespace: yes
It works fine now. All imap_ns_* parameters are set to null in main.inc.php.
Thanks for your help.
Julien _______________________________________________ List info: http://lists.roundcube.net/users/ BT/9b404e9e