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#425 receipt on delivery implemented in non-standard way

Tomas Kuliavas

SquirrelMail uses Return-Receipt-To: header which is
not standard.

I think, rfc3461 states that delivery notification
should be used only if email server informs about DSN
support in EHLO response.

/usr/sbin/sendmail enables notification, if '-N dsn'
option is used.


    • assigned_to: nobody --> jangliss
  • Logged In: YES

    I did a google a bit for this. I managed to uncover this:


    It mentions RFC2822, which we try to comply with, but also
    mentions the header is non-standard. There were several
    other mentions of the headers causing issues on the Exim
    mailing lists. I'll take a look at RFC3461, and find out
    what I can work out.

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    Random question, but DSN is supposed to be an end server
    thing isn't it? If so, how is SM going to know that DSN is
    enabled, if the end server isn't the one it connects to? Or
    am I missing the point?

  • Tomas Kuliavas
    Tomas Kuliavas

    Logged In: YES


    5.2.2 Relay of messages to non-conforming SMTP servers

    dsn message is handled by last DSN conforming server.
    according to rfc.

    Personally I (qmail user, no rfc3461 support, dsn
    implemented in djb way with extra delivery programs) preffer
    options would allow removing server side dsn completely and
    leaving client side dsn turned on/controled by end user.

    If server's support rfc3461 and user asks for delivery
    reciept, squirrelmail appends special tags to user's address.

    If user asks for delivery reciept and used smtp server does
    not declare DSN support in EHLO, squirrelmail should prevent
    from using this feature or revert to old "add extra header" way.

  • Logged In: YES

    I'm a bit confused here. What's exactly the status of this
    bug? Does it need to be fixed?

  • Tomas Kuliavas
    Tomas Kuliavas

    Logged In: YES

    SquirrelMail uses Return-Receipt-To: header to implement
    receipt on delivery. RFC states that it should use rcpt to:
    when SMTP server informs about DSN support in EHLO response.
    It should not use server side dsn, when server does not
    inform about it.

  • Tomas Kuliavas
    Tomas Kuliavas

    • labels: 102905 -->