high cpu usage on natd / dhcpd

[Sasha]

I've got the same issue - heavy CPU load of natd and dhcpd processes :(
I bought Intel PRO/1000 PT Dual Port Server Adapter (82571) to my home
server. I also noticed big loopback transfers on lo0 iface.
If I connect and work from WAN (em0) it's dropping packets and hangs for
some time, even disconnecting me, if I work from within LAN (em1) than 
works fine.

My system: FreeBSD 8.3-PRERELEASE

# systat -ifstat

                 /0   /1   /2   /3   /4   /5   /6   /7   /8   /9   /10
  Load Average   ||||||||||||||||||||||||

     Interface           Traffic               Peak                Total
         lo0  in      2,442 MB/s          2,442 MB/s           21,871 GB
              out     2,442 MB/s          2,442 MB/s           21,871 GB

         em1  in      0,044 KB/s          0,044 KB/s            1,185 GB
              out     0,061 KB/s          0,061 KB/s           68,261 GB

         em0  in      0,089 KB/s          0,212 KB/s           65,451 GB
              out     0,730 KB/s          0,730 KB/s            1,103 GB


Any solutions?...

S.