Problem with someone port scanning me

[Dragoncrest]

	For the past couple of days I've had someone on our lan port scanning my 
box.  Not sure what's up with that, but I'm curious if there's a way to log 
what IP address this is coming from.  I don't have IPFW enabled yet as I 
haven't had the time to configure it at this point as it's currently behind 
the company firewall on our T3.  Is there a way to log where it's coming 
from?  Or is that already being logged somewhere?