logging all access by IP

I set up a squid box with sarg to run along my MT router. This box is listening on port 3128, I made 2 rules so I can redirect all the traffic to this box:

chain=dstnat src-address=172.16.0.1 protocol=tcp dst-port=80 action=accept



chain=dstnat in-interface=bridge src-address=!172.16.0.1 protocol=tcp 
     dst-port=80 src-address-list=everyone action=dst-nat 
     to-addresses=172.16.0.1 to-ports=3128

My MT box is 172.16.0.254 and my Squid box is 172.16.0.1. Unfortunatelly this isn’t working, the traffic is passing by without being cached.
I don’t want to use the web-proxy with parent-proxy because squid only logs the IP of the MT box. I need to see what IP accessed what on port 80.

Any ideas on what could be wrong?