[Dovecot] IMAP clients generate user home folders one level higher than needed

[andel]

Hi

(Of course not the clinets generate the folders, dovecot does, but I wanted
to have the title not be too long.)

I am using static userdb:

userdb static {
  args = uid=vmail gid=mail home=/srv/vmail/%d/%n
}

and I have configured the hostname in protocol lda.

Now when mail arrives for a known virtual user, the home directory with all
subdirectories is being created correctly unter /srv/vmail/$domain/$vuser.

But when connecting from an IMAP client (I have tested Thunderbird and
Outlook) a new home directory with apparently correct subfolders is bring
created unter /srv/vmail/$vuser ! The connection works, I just don't see
the mails which arrived since the client is mapping a directory one level
higher than needed.

Where do I have to look for the cause? I did not find anything reasonable
yet.

Thank you in advance,
David