[Dovecot] Virtual Users and permission denied on POP3 Authentication - cur directory

[John Dubchak]

Hi,

I've been working on configuring a new Postfix+Dovecot+Cyrus-SASL 
+Postgres server to perform multi-domain virtual hosting with non-unix  
accounts.  I believe I have everything working correctly and have  
tested both the SASL portion and POP authentication through telnet and  
all works as expected, with one exception.

When I authenticate using POP3:

# telnet mail.host 110
Trying 192.168.XXX.XXX...
Connected to mail.host.
Escape character is '^]'.
+OK Dovecot ready.
user user1 at domain1.com
+OK
pass secret
+OK Logged in.
-ERR No INBOX for user.

And the maillog reports the following:

Jan 21 13:42:32 mail.host dovecot: pop3-login: Login: user=<user1>,  
method=PLAIN, rip=192.168.XXX.XXX, lip=192.168.XXX.XXX
Jan 21 13:42:32 mail.host dovecot: POP3(user1): mkdir(/var/spool/ 
virtual_mailbox/domain1.com/user1/cur) failed: Permission denied
Jan 21 13:42:32 mail.host dovecot: POP3(user1): mkdir(/var/spool/ 
virtual_mailbox/domain1.com/user1/cur) failed: Permission denied
Jan 21 13:42:32 mail.host dovecot: POP3(user1): Couldn't open INBOX:  
Internal error occurred. Refer to server log for more information.  
[2008-01-21 13:42:32]
Jan 21 13:42:32 mason dovecot: POP3(user1): No INBOX for user top=0/0,  
retr=0/0, del=0/0, size=0

The directory structures for the virtual mailboxes are:

/var/spool/virtual_mailbox/domain1.com/user1
/var/spool/virtual_mailbox/domain2.com/user1

And the entire tree from virtual_mailbox down is owned by  
vuser:vuser.  The directories have permissions 700.

What I believe is happening is that Dovecot is trying to use the uid  
and gid of user1, who doesn't have a system account, rather than  
vuser's when writing to the virtual_mailbox folders.  I'm not sure how  
I can configure Dovecot to use the vuser information.

Here is my dovecot.conf:

-------------------------------------------------------------------------
protocols = imap pop3
listen = [*]
disable_plaintext_auth = no
syslog_facility = mail

mail_location = maildir:/var/spool/virtual_mailbox/%h

# Default umask to use for mail files and directories.
#umask = 0077

protocol imap {
}

protocol pop3 {
}

protocol lda {
   postmaster_address = postmaster at example.com
}

auth_debug_passwords = yes
auth_debug = yes
auth_verbose = yes
auth default {
   # SQL database
   passdb sql {
     args = /etc/dovecot-sql.conf
   }

   userdb sql {
     args = /etc/dovecot-sql.conf
   }

   user = root
}
-------------------------------------------------------------------------

Any insight will be appreciated, I've been working on this non-stop  
for several days now and can't seem to figure it out.

Thanks,
John