[Exim] Killing a misconfigured host.

Every day my server logs have multiple entries showing:

rejected HELO from [192.147.174.218]:
syntactically invalid argument(s): bog.lodo.exactis.com'

These seem to come from various IP addresses.

I presume Exim is complaining about the spurious ' on the end of
the hostname ?

What's the quickest way to kill this attempted delivery, assuming
all the messages arise from multiple attempts to deliver the same
message ?

I'm tempted to try and receive it, just to find out to which local user
it is aimed.

BTW, emailing postmaster@??? fails due to a broken
alias :-(

I have emailed postmaster@???, who seem to have
taken over the exactis.com domain, but I've heard zip so far.

Adrian Harris
Postmaster
Reading College and School of Arts and Design.