Bridge transparent proxy

[Antonio Tommasi]

Hi to all i'm trying to installa a bridge transparent proxy on a 
freebsd 6.2 with ipfw and squid.
I have two machine;
  on the first one i've enabled option bridge in kernel option and 
then i've recompile it and set variable sysctl in /etc/sysctl.conf
on the second i've set bridge_load module on the boot/loader.conf and 
set the same variable from above in /etc/sysctl.conf
Naturally i've used the correct name of network interface in the 
configuration file on the two machine.
I've the same configuration in firewall rules and squid in the two machine.
It works only on the machine with the kernel recompiled with bridge module.
Somebody can help me?
Thanks in advance
Antonio