I am finding subscribers' ISP that use Symantec_AntiVirus_for_SMTP_Gateways very annoying esp. with these "delayed" type messages sent back to list-owners: Your message with Subject: blah-blah-blah could not be delivered to the following recipients: [RFC822 address] Please do not resend your original message. Delivery attempts will continue to be made for 5 day(s).