[Mailman-Users] A long URL - 2 lines - second line is not clickable.

Richard Barrett R.Barrett at ftel.co.uk
Tue Aug 20 17:47:31 CEST 2002

At 09:22 19/08/2002 -0700, Wang, Mary Y wrote:
>I am using Mailman 2.0.6-1 and Sendmail-8.11.6-3.  My users are complaining
>about the line wrap problem when send mailing mail to the mail list with a
>long URL.  It seems line wraps text lines that are longer than 80 characters
>with no white-space.  If you include a long URL in a email message it
>usually gets split onto separate lines and the typical email reader within
>BCA (exchange) marks the first part of the link as clickable when usually it
>isn't.  People have to paste the whole link back together manually in a web
>browser input dialog to get it to work.
>First, I thought it maybe a Sendmail problem. So I tried send a mail via
>Sendmail with a long URL and it appears to be fine.  The long URL did split
>into two lines, and the second line is still highlighted as a href link, so
>there was no problem.  By clicking the link, the browser would bring up the
>correct information.
>However, sending an email to the mail list is a different problem.
>For example,
>_02.html will show up with 2 lines and the second line would be ml and
>wouldn't be highlighted as part of the URL that is clickable.
>Any clue?
>Thanks for any help.  We had this problem for about a year.  I finally got a
>chance to look into it now.
>(562) 797-1545

I suspect at the back of this is what RFC2822 says and how some Mail Agent 
code/configuration is interpreting the RFC:

2.1.1. Line Length Limits

    There are two limits that this standard places on the number of
    characters in a line. Each line of characters MUST be no more than
    998 characters, and SHOULD be no more than 78 characters, excluding
    the CRLF.


    The more conservative 78 character recommendation is to accommodate
    the many implementations of user interfaces that display these
    messages which may truncate, or disastrously wrap, the display of
    more than 78 characters per line, in spite of the fact that such
    implementations are non-conformant to the intent of this
    specification (and that of [RFC2821] if they actually cause
    information to be lost). Again, even though this limitation is put on
    messages, it is encumbant upon implementations which display messages


Mailman doesn't appear to fool with the line breaks in email sent to it for 
redistribution. Its internal archiver also appears to behave sensibly when 
processing long line into HTML archives files by only word wrapping long 
lines on white space to a reasonable length so that the <PRE> tagged 
message text displays sensibly with a web browser. So your long URL would 
survive intact transit through and archiving by MM. It certainly does on my 
MM system.

Sendmail can be configured to limit line length so some MTA through which 
your mail is passing could be limiting line length though usually it will 
be to the 990 character limit.

The MUA from whence the long URL originated is possible culprit.

The fact is that the RFC admits the possibility of line length manipulation 
by Mail Agents although it could be regarded as anti-social to use the 78 
char limit. The only way to ensure line break changes do not corrupt your 
data is to base64 encode it; not the most convenient solution, I grant you.

More information about the Mailman-Users mailing list