Martian sources from localhost

[Rich Stanton <stantonrj@Cf.ac.uk>]

I've got a machine running sarge, with a guarddog configued firewall. 
I'm getting some related messages in my logs:

Apr 19 09:27:17 localhost kernel: martian source local.ip from local.ip, 
on dev eth0
Apr 19 09:27:19 localhost kernel: martian source broadcast.ip from 
local.ip, on dev eth0

and
Apr 19 09:27:17 localhost kernel: ll header: 
ff:ff:ff:ff:ff:ff:00:10:eth0:mac:address:08:06

I understand why these are martian sources - they're coming from the 
broadcast address to my local machine.  However do they indicate a 
misconfiguration on this local machine, or should I just ignore them? 
No other machine on the network is getting these events logged.