HP TCP/IP Services for OpenVMS Release Notes

Corrections4.11 SMTP Problems Fixed in This Releasetime, the host has taken responsibility for the message and, if there is a problemdelivering the message, must bounce the message itself.This behavior is more problematic when the system receives SPAM. SPAM arriveson the host for a non-existent user and is bounced by the host’s symbiont processto the email address in the SPAM’s Return-Path: header. The SPAM’s Return-Path: header contains an invalid email address, so the bounced SPAM is in turnbounced back to the host’s POSTMASTER account. The POSTMASTER account’smail is forwarded to the SYSTEM account, which means that the SYSTEM usermust constantly separate these doubly-bounced SPAMs from their valid email.Solution:The SMTP receiver has been changed to check to see if the recipient emailaddress in the RCPT TO SMTP protocol command is deliverable. This solves theproblem by not letting the SPAM for the unknown user onto the host in the firstplace.The Symbiont-Checks-Deliverability configuration option allows you to turnthis feature on and off. Enter this configuration option in the SMTP configurationfile (SMTP.CONFIG).When this option is set to TRUE, the symbiont checks deliverability of RCPTTO recipients. Setting Symbiont-Checks-Deliverability to FALSE (the default)tells the receiver to check the deliverability4.11.2 SMTP Accepts Mail from Senders Who Should Be BlockedProblem:SMTP might accept mail from senders who should be blocked. These are senderslisted in the anti-SPAM Reject-Mail-From field of the SMTP.CONFIG file. SMTPfails to block such mail when the entries in the Reject-Mail-From field exceedthe 500-character limit for SMTP.CONFIG fields.Solution:This problem is corrected in this release. HP has increased the character limitfor fields in the SMTP.CONFIG file from 500 to 10,000.4.11.3 Two Messages Acquire Same Value in Message-ID HeaderProblem:Any two messages composed in the same one-hundredth of a second will acquirethe same value in their Message-ID header. This can cause some mail systemsto delete the second of the two messages as a duplicate. Message-IDs should beunique.Solution:This problem is corrected in this release. Any two messages created in thesame one-hundredth of a second will acquire unique values in their Message-IDheaders.4–10 Corrections