Re: Subject line in Mailto forms

Arnoud (
Sun, 15 Jun 1997 11:35:36 +0200

From: (Arnoud "Galactus" Engelfriet)
Subject: Re: Subject line in Mailto forms
Date: Sun, 15 Jun 1997 11:35:36 +0200
Message-ID: <>

In article <v03102804afc904073e80@[]>,
Walter Ian Kaye <> wrote:
> At 8:41p +0200 06/13/97, Arnoud "Galactus" Engelfriet wrote:
>  > [the ?subject= hack on mailto]
>  > It was, but someone wrote up a draft RFC so it's going to become an
>  > Internet standard.. ;-(
> Please refresh my memory -- what was the problem? Some sort of conflict?

There are several problems:

1) it breaks all other clients, as RFC 1738 defines the value of
mailto to be an email address only. Thus, mail from those clients
will bounce, as "" is not a valid host.
2) Adding other headers in the same way is tricky
3) You have to URL-encode the value of the subject line, which
few people will do, as it's not intuitive.
4) You only have 1024 characters for subject and other headers (assuming
you do 2).

> Wouldn't %-escaping cover any conflicts?

It would only solve problem 3. A much better solution IMO would be

<A HREF="">Mail me!
<PARAM NAME=subject VALUE="Look ma, a really long subject,
and it's not even URLencoded!">
<PARAM NAME=x-silly-header VALUE=Yeah..whatever>

or perhaps adding an attribute a la USEMAP (USEAPP? PARAMLIST?)
to A that links to a list of parameters, then you could even re-use
the information in multiple mailto links.

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