smtpd_sender_restrictions =                                             
  permit_mynetworks,
  permit_sasl_authenticated,
  reject_non_fqdn_hostname, 
  reject_non_fqdn_sender,  
  reject_non_fqdn_recipient,
  reject_unauth_destination,
  reject_unauth_pipelining, 
  reject_invalid_hostname,    
  reject_rbl_client opm.blitzed.org,
  reject_rbl_client list.dsbl.org,   
  reject_rbl_client bl.spamcop.net,  
  reject_rbl_client sbl-xbl.spamhaus.org