Can't PING because i've got a NAT ISSUE =(

[k o u b]

   At the startup of my FreeBSD 5.3 (mini-install), i've got two mess
   about NAT:

   Warning: enable NAT: Invalid command
   Warning: enable nat: Failed 1

   after, i've got the mess "fxp0: device timeout"

   TIA


   koub. :)