postfix, sasl2 and imapd realm problem

[redel]

dear list,

I'm using:
postfix-1.1.12-20021202
cyrus-sasl-2.1.7
cyrus-imapd-2.1.9

my requirements:
managing a single mail domain (f.ex. foo.com) with imap,
with auth CRAM-MD5 or DIGEST-MD5. (no plain text passwords
and others)

what I did:
- turned on unixheirsep to allow dots in mbox-names
- created the mailbox for each user with
cm [EMAIL PROTECTED]
- run saslpasswd2 with -u foo.com -c user
to have the domain name as realm
- used auxprop as generel pw-check method.
(for postfix-smtpd and imapd)
(I tested the above configuration with my mailer:
I could see my Inbox and auth with CRAM-MD5 to
my mailbox-account [EMAIL PROTECTED] also worked correctly)

- configured postfix-smtp using CRAM-MD5 or DIGEST-MD5
and lmtp socked for mailbox_transport to imapd.

my problem:
with the above configuration, postfix cannot send mail
to the users mailboxes: I get the follwoing error:

Dec 10 20:38:35 linux postfix/lmtp[1657]: 127871E7BD: to=<[EMAIL PROTECTED]>, relay=/var/spool/postfix/public/lmtp[/var/spool/postfix/public/lmtp], delay=0, status=bounced (host /var/spool/postfix/public/lmtp[/var/spool/postfix/public/lmtp] said: 550-Mailbox unknown. Either there is no mailbox associated with this 550-name or you do not have authorization to see it. 550 5.1.1 User unknown (in reply to RCPT TO command))


ok, the mailbox [EMAIL PROTECTED] cannot be found. when creating
mbox names in imap containing the plain user name only (without the domain name extension @foo.com) postfix can deliver the mail correctly, but then, my imap-client cannot see his Inbox anymore.

For me, the main problem in the whole story seems to be, that sasl passwords cannot be created without a realm. or is there a possibility that I have not seen yet? maybe I can tell postfix in the cyrus part within the deliver parameter to define the correct mailbox name as defined in my imap environment???
my current deliver call is:
usr/lib/cyrus/bin/deliver -e -r ${sender} -m ${extension} ${user}

I studied the mails in this list and found people who had similar problems with auth and realms. Has anyone in the list solved this problem till now or any suggestions?? comments would be highly appreceated.

my workaround:
I created 2 mboxes for each user: one containig the complete domain
in the mbox name ([EMAIL PROTECTED]) and the other with the username
only (hello). so postfix can deliver mail to hello an my imap client can see his Inbox. In order to get the 2 boxes together I deleted the mbox dir hello in /var/spool/imap/user and created a link:
ln -s hello@foo^com hello
It worked well within my short tests. but what happens in a production environment?? may I get serious problems that I can't see yet?

many thanks in advance.

reinhold