[CentOS] Huge mailq

> /etc/init.d/sendmail stop
> chkconfig --level 2345 sendmail off
> find /var/spool/mqueue -type f -exec rm -f {} \;
> 
> That'll empty out your queue and you won't have to worry about
> it building up again, pesky thing!
> 

Hmm...it will still build. To really fix it, you need to do one more step:

rpm -e --nodeps sendmail

Now that is a permanent solution.