Logwatch spammer question?

["Knute Johnson" <knute@xxxxxxxxxxx>]

**Unmatched Entries**
    ruleset=check_relay, arg1=59-112-82-90.dynamic.hinet.net,
    arg2=59.112.82.90, relay=59-112-82-90.dynamic.hinet.net
    [59.112.82.90], reject=550 5.0.0 Die spammer die!: 1 Time(s)

These guys and a few others try to relay through my mailserver almost 
everyday.  Do they think that someday I'm going to mess up and have 
my relay open?  This has been going on for over a year.  Just curious 
if others see these things too.

Thanks,

-- 
Knute Johnson
Molon Labe...