Cyrus Virtual Domains Login Problem

Cyrus POP3 Login Error:

[root@ ~]# telnet localhost 110
Trying 127.0.0.1...
Connected to localhost.localdomain (127.0.0.1).
Escape character is '^]'.
+OK centos.domain.com Cyrus POP3 v2.3.7-Invoca-RPM-2.3.7-1.1.el5 server ready <3974298939.1192619430@centos.domain.com>
user user@domain.com
+OK Name is a valid mailbox
pass password
-ERR [AUTH] Invalid login
quit
+OK
Connection closed by foreign host.

To allow '@' in username during login, edit imapd.conf and set virtdomains: yes

[root@ ~]# nano /etc/imapd.conf
postmaster: postmaster
configdirectory: /var/lib/imap
partition-default: /var/spool/imap
#admins: cyrus # no admins!
virtdomains: yes
allowanonymouslogin: no
allowplaintext: yes
sendmail: /usr/sbin/sendmail
hashimapspool: true
sasl_pwcheck_method: saslauthd
sasl_mech_list: PLAIN
servername: centos.domain.com
autocreatequota: 10000
reject8bit: no
quotawarn: 90
timeout: 30
poptimeout: 10
dracinterval: 0
drachost: localhost
sievedir: /var/lib/imap/sieve
sieve_maxscriptsize: 32
sieve_maxscripts: 5
##unixhierarchysep: yes
tls_ca_file: /etc/pki/cyrus-imapd/cyrus-imapd.pem
tls_cert_file: /etc/pki/cyrus-imapd/cyrus-imapd.pem
tls_key_file: /etc/pki/cyrus-imapd/cyrus-imapd.pem

Restart cyrus-imapd:

service cyrus-imapd restart

Test IMAP login:

/usr/bin/imtest -a user@domain.com -w password localhost