dovecot - Mar 2013 - postfix+dovecot+samba4+openldap: dovecot lda:Error: user sammy: Initialization failed: mail_location not set and autodetection failed

I'm trying to setup a samba4 with openchange which uses
postfix+dovecot+openldap on a ubuntu 12.04.2 system. I can send outgoing
emails but incoming emails fail. I looked up the logs and I get:

Mar  5 11:03:48 testerA dovecot: lda(sammy): Error: user sammy:
Initialization failed: mail_location not set and autodetection failed:
Mail storage autodetection failed with home=/var/mail
Mar  5 11:03:48 testerA dovecot: lda(sammy): Fatal: Invalid user
settings. Refer to server log for more information.

any idea what I am doing wrong?  Any hints,  pointers would be much
appreciated.


now the user is a virtual user. The /var/mail/sammy exists:

drwxr-sr-x 10 vmail vmail 4096 Mar  4 13:48 sammy
lrwxrwxrwx  1 vmail vmail    5 Feb 28 12:12 Sammy -> sammy
lrwxrwxrwx  1 vmail vmail    5 Feb 28 12:12 sammy at abertax.com -> sammy
lrwxrwxrwx  1 vmail vmail    5 Feb 28 12:13 Sammy at abertax.com -> sammy
lrwxrwxrwx  1 vmail vmail    5 Mar  1 15:05 sammy at abx.abertax.com -> sammy


The dovecot configuration is:

# 2.0.19: /etc/dovecot/dovecot.conf
# OS: Linux 3.2.0-38-generic x86_64 Ubuntu 12.04.2 LTS ext4
disable_plaintext_auth = no
lda_mailbox_autocreate = yes
lda_mailbox_autosubscribe = yes
log_path = /var/log/dovecot.message
log_timestamp = "%Y-%m-%d %H:%M:%S "
mail_debug = yes
mail_location = maildir:/var/mail/%u
mail_privileged_group = mail
passdb {
  driver = pam
}
passdb {
  args = /etc/dovecot/dovecot-ldap.conf
  driver = ldap
}
passdb {
  driver = pam
}
protocols = imap
service auth {
  unix_listener auth-master {
    group = vmail
    mode = 0600
    user = vmail
  }
  unix_listener auth-userdb {
    user = vmail
  }
  user = root
}
ssl_cert = </etc/ssl/certs/dovecot.pem
ssl_key = </etc/ssl/private/dovecot.pem
userdb {
  driver = passwd
}
userdb {
  args = /etc/dovecot/dovecot-ldap.conf
  driver = ldap
}
userdb {
  driver = passwd
}
protocol lda {
  hostname = abx.abertax.com
  info_log_path = /var/log/dovecot.info.log
  log_path = /var/log/dovecot.message
  postmaster_address = postmaster at mydomain
}
protocol pop3 {
  pop3_uidl_format = %08Xu%08Xv
}

and dovevot-ldap.conf:

uris = ldap://localhost:3389
dn = cn=admin,dc=mydomain
dnpass = openchange
tls = no
ldap_version = 3
base = dc=mydomain
scope = subtree
user_attrs = homeDirectory=home,uidNumber=uid,gidNumber=gid
user_filter = (uid=%u)
pass_attrs = uid=user,userPassword=password
pass_filter = (uid=%u)

Thanks
Sammy