sender verify callout

I have a number of messages in my SMTP that have gotten "stuck" I am getting the error message
" Could not complete sender verify callout (in reply to RCPT TO command"

We have setup this server as STRICTLY an smtp server that is send mail relayed to it by our main mailserver.

here is the postconf -n
let me know if there is anyother info needed...

alias_maps = hash:/etc/aliases,hash:/var/mailman/data/aliases
command_directory = /usr/sbin
config_directory = /etc/postfix
content_filter = smtp-amavis:[127.0.0.1]:10024
daemon_directory = /usr/libexec/postfix
debug peerlevel = 2
enable serveroptions = yes
html_directory = no
inet_interfaces = all
mail_owner = postfix
mailbox sizelimit = 0
mailbox_transport = cyrus
mailq_path = /usr/bin/mailq
manpage_directory = /usr/share/man
message sizelimit = 12582912
mydestination = $myhostname,localhost.$mydomain,localhost,smtp.memphisflyer.com
mydomain = memphisflyer.com
mydomain_fallback = localhost
myhostname = memphisflyer.com
mynetworks = 127.0.0.1/32,192.168.0.0/24,214.37.68.42,192.168.0.245
mynetworks_style = host
newaliases_path = /usr/bin/newaliases
owner requestspecial = no
queue_directory = /private/var/spool/postfix
readme_directory = /usr/share/doc/postfix
recipient_delimiter = +
sample_directory = /usr/share/doc/postfix/examples
sendmail_path = /usr/sbin/sendmail
setgid_group = postdrop
smtpd pw_server_securityoptions = gssapi,cram-md5,plain,login
smtpd recipientrestrictions = permit sasl_authenticated,permit_mynetworks,reject_unauthdestination,permit
smtpd sasl_authenable = yes
smtpd tls_keyfile =
smtpd use_pwserver = yes
transport_maps = hash:/etc/postfix/transport
unknown local_recipient_rejectcode = 550