[exim] Exim drops mails

Hi all

I have the strangest problem, all of a sudden my mail server started to
drop mails with more than 100 recipients in the it, the error in the
logs that I get is "unexpected disconnection while reading SMTP command
from"

Any idea's, I think this might have happened after a mail shot of about
5000 mails but this has long gone, If I don't have to bounce the server
I really do not want to.

Thanks in advance
Peter