spammer using my mail server send spam email
there days, i found one spammer who sent a lots of spam mails via my email server
i have configured sendmail with auth for relay, i don't know how does spammer can do it?
if he cracked my user's username&password, how can i track it in log file /var/log/maillog ?? there are no "authid= ??" in the log file. very stranges
hope someone can help me.
thanks a lot