procmail
[Top] [All Lists]

Re: X-UIDL

1997-09-12 23:44:15
"Karsten W. Rohrbach" <rohrbach(_at_)nacamar(_dot_)net> writes:
to keep the thread up, did somebody, by chance, get any new info on the
"X-UIDL:" header? i looked through some rfc's and pop3 related docs but i
couldnt find anything. 

*       It's not standardized, and will never be standardized by an RFC.
        (No X- header can be)

*       Some servers use this to store information for the UIDL command.

*       Some clients apparently store UIDL information in this header
        in the locally downloaded copy.  (Note: the POP3 protocol doesn't
        let the client modify the message(s) stored on the server.)

*       Some spamming software packages include this header in messages
        they send to make some POP3 clients that support client side
        filtering think that they've already filtered the message.

*       Filtering out incoming messages (pre-retrieval via POP3) seems
        'fairly' safe, though some legitimate mail may include this
        header.  Using it as a heavy weight (but not enough on it's own)
        in a procmail scoring recipe that detects spam appears to be
        reasonable.

Philip Guenther