loadbalance weird with freebsd client

[sukaca]

i'm using freebsd 6.1 for balancing.
after balancing server it has server as transparent proxy and gateway.
this is the diagram balance ---proxy/gw(using linux)----client.
the problem is.whan i use this configuration.
balance---proxy---pfsense----client.
this is the result of traceroute

192.168.20.1 (192.168.20.1)  10.396 ms  7.525 ms  8.708 ms
 2  192.168.1.222 (192.168.1.222)  4.327 ms  8.627 ms  4.925 ms
 3  192.168.3.1 (192.168.3.1)  9.981 ms
    192.168.5.1 (192.168.5.1)  10.025 ms
    192.168.3.1 (192.168.3.1)  10.594 ms

thereis  3.1,4.1,5.1 and 6.1 as dsl modem ip.
that one reason why proxy/gw is using linux.
because whan i using freebsd it has the same result of traceroute.
trace by linux

192.168.20.1 (192.168.20.1)  10.396 ms  7.525 ms  8.708 ms
 2  192.168.1.222 (192.168.1.222)  4.327 ms  8.627 ms  4.925 ms
 3  192.168.3.1 (192.168.3.1)  9.981 ms
 4  203.77.212.20 (internet)


thank you for advance

regard
vicky