US Patent 7093025 SMTP extension for email delivery failure

The present invention provides in a computing system including an email system connected to an email network using the SMTP (Simple Mail Transfer Protocol) protocol, a method for specifying alternate email recipients comprising:specification of alternate recipients by the sender of an email message to be used in case the mail system can not deliver the message to the original recipient,delivery of the message to the specified alternate recipients by the email system in case it is unable to deliver to the original recipient.