[exim] limiting subject line length?

Hi there,

Some of our users have decided that its a great idea to put their *entire*
email message into the subject line even when it is several paragraphs long.

(Some of these users do this and have email sigs which are also several
paragraphs long so the email consists of a gigantic subject 'line' and the
body of the email is just a huge 'disclaimer' sig, but I digress).

Is there a nice way to limit subject line length to discourage this practice?

For reference, this is exim4 under Debian.

Thanks!



--
Please remember that an email is just like a postcard; it is not
confidential nor private nor secure and can be read by many other people
than the intended recipient. A postcard can be read by anyone at the mail
sorting office and expecting what is written on it to be private and secret
is not realistic. Please hold no higher expectation of email.

If you need to send confidential information in an email you need to use
encryption. PGP is Pretty good for this.