strange authentication behaviour with sasldb2 / auxprop

[Peter Markom]

Hi, it's me again  ;-)    :-(

I try to authenticate cyrus-imap via sasl-auxprop and /etc/sasldb2.

problem is:

user: nospam at master.koordinaten.at  ->  authentication works fine

user: nospam at koordinaten.at  		-> authentication fails (badlogin: user not 
found)

I do not understand why this happens nor what I have to do to change it 
(all I care about is to authenticate nospam at koordinaten.at).

Hostname = master.markom.at (which is also what the IP-adress resolves 
to).
Default-Domain is "koordinaten.at".

master:~ # sasldblistusers2
nospam at koordinaten.at: userPassword
nospam at master.koordinaten.at: userPassword

master:~ # cat /etc/imapd.conf
configdirectory: /var/lib/imap
partition-default: /var/spool/imap
sievedir: /var/lib/sieve
admins: cyrus
allowanonymouslogin: no
autocreatequota: 100000
reject8bit: no
quotawarn: 90
timeout: 30
poptimeout: 10
dracinterval: 0
drachost: localhost
sasl_pwcheck_method: auxprop
sasl_mech_list: login plain
allowplaintext: no
allowapop: no
lmtp_overquota_perm_failure: no
virtdomains: userid
defaultdomain: koordinaten.at
tls_cert_file: /var/lib/imap/server.pem
tls_key_file: /var/lib/imap/server.pem


/var/spool/imap looks like this:

/var/spool/imap/
---> user ---> nospam   (= nospam at koordinaten.at)
---> stage.
---> domain ---> master.koordinaten.at ---> user ---> nospam 
(=nospam at master.koordinaten.at)


As always, any hints are greatly appreciated.

bye

Peter