hi I have the same problem and i think it is messing around some services running on my dmz. I'm having those same errors but in my case i have a pfsense server with 3 interfaces: lan , wan and dmz atached to 3 differents switches. Then i have this other server(a linux box running suse) with only 2 interfaces atached to LAN and DMZ along with the pfsense box. I receive a lot off this messages . The problem is that my pfsense box is the default GW and when client on LAN tryies to comunicate with services running on the linux server but on the "DMZ" side is when i receive those messages. Pfsense knows linux server IS on DMZ (by destination's ip) but receives replies on LAN side. How can i solve this?. I'm thinking this should not be a pfsense issue, but before i put the pfsense I had a linux box running as a gateway , router and proxy, and didn't have this problems, since I installed pfsense I'm having users reporting problems when trying to communicate with services on the DMZ side of my linux box, they can connect but connection is lost after a while. Then they reconnect fine but the connections drop again.
Tks for your help and sorry for the long post.
Running Pfsense 1.2.2
Fito
Asuncion-Paraguay