Sendmail applet may need to validate on RCPT

[Gustavo Zacarias]

Hi.
There's a missing scenario in the sendmail applet.
In some cases AUTH LOGIN must be forced in order to relay mails thru a
server.
My particular scenario is a sendmail (proper) server that wants auth to
relay to foreign domains.
Example:

220 somedomain.com ESMTP Sendmail; Fri, 27 Mar 2009 11:42:34 -0300
MAIL FROM: user at somedomain.com
250 2.1.0 user at somedomain.com... Sender ok
RCPT TO: otheruser at gmail.com
550 5.7.1 otheruser at gmail.com... Relaying denied. Proper authentication
required.

Problem is you can't issue an AUTH LOGIN after a MAIL FROM has been
issued, so a command-line switch to issue the auth command would be
required.
Or maybe i'm missing something?
I can chew a patch if this would be the preferred way, basically moving
out the MAIL FROM/AUTH check in sendmail.c to a new opt.
Regards.