I get the following error on auth with mysql on pop3
what am i missing or doing wrong

mysql config file

db_host = localhost
#db_port = 3306
db_unix_socket = /var/lib/mysql/mysql.sock
db = ADMIN
db_user = mailmaster
db_passwd = ********
db_client_flags = 0
default_pass_scheme = PLAIN
password_query = SELECT MAILBOX_PASSWORD AS password FROM MAIL WHERE MAILBOX_USERNAME = '%n' AND MAILBOX_DOMAIN = '%d'
#user_query = SELECT MAILBOX_ROOT AS home,uid,gid FROM MAIL WHERE MAILBOX_USERNAME = '%n' and MAILBOX_DOMAIN='%d'

dovecot config file
base_dir = /var/run/dovecot/
protocols = imap pop3
imap_listen = *
pop3_listen = *
ssl_disable = yes
log_path = /var/log/dovecot_log
info_log_path = /var/log/dovecot_info_log
log_timestamp = "%b %d %H:%M:%S "
login_dir = /var/run/dovecot/login
login = imap
login_executable = /usr/local/libexec/dovecot/imap-login
login_user = dovecot
login_process_size = 16
login_process_per_connection = yes
login_processes_count = 3
login_max_processes_count = 128
login_max_logging_users = 256
login = pop3
max_mail_processes = 1024
verbose_proctitle = no
first_valid_uid = 500
#last_valid_uid = 0
default_mail_env = maildir:/home/mail/%d/%n/Maildir
mail_cache_fields = MessagePart
client_workarounds = oe6-fetch-no-newmail:outlook-idle:
mailbox_check_interval = 300
mailbox_idle_check_interval = 30
mail_save_crlf = yes
mail_read_mmaped = no
maildir_copy_with_hardlinks = yes
mbox_locks = dotlock fcntl
mbox_read_dotlock = yes
mbox_lock_timeout = 120
mbox_dotlock_change_timeout = 30
umask = 0077
mail_drop_priv_before_exec = no
imap_executable = /usr/local/libexec/dovecot/imap
imap_process_size = 256
pop3_executable = /usr/local/libexec/dovecot/pop3
pop3_process_size = 256
auth = default
auth_mechanisms = plain
auth_passdb = mysql /usr/local/etc/dovecot-mysql.conf
auth_user = mailmaster
auth_username_chars = abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@