exim and bad Sender: header

[Carl Johnson <carlj@peak.org>]

I have received 2 bad debian-user messages in the past couple of days
that have held up my mail system.  In both cases fetchmail received
the message, but exim rejected it, which then caused fetchmail to quit
without deleting the message.  In both cases it appeared to be a
message with a header similar to the following:
   Sender:  "First Last" <>

I ended up with the following fetchmail messages:
reading message 1 of 31 (1088 header bytes) .fetchmail: SMTP error: 501 <@kira.peak.org> : colon expected after route
fetchmail: SMTP error: 501 <carlj> : sender address must contain a domain
fetchmail: SMTP transaction error while fetching from kira.peak.org

The exim rejectlog had the following message:
unqualified sender rejected: <carlj> H=cjlinux.localnet [192.168.191.2] (carlj)

The header appears to be invalid since it only has a name but no email
address.  In both cases I ended up manually logging in to my ISP and
deleting the message.  Should either fetchmail or exim do something
more productive than just halting, or am I totally out of luck when
somebody mis-configures their system like that?  Since this was
debian-user, should the mailing list try to filter out invalid headers
like this?  I am running hamm with versions exim_1.92-3 and
fetchmail_4.3.9-1, so are there newer versions which handle this type
of situation better?

I would really like to get this fixed, since I have my system
automatically pick up mail, but this totally halts that.  Thanks in
advance for any help.

-- 
Carl Johnson		carlj@peak.org