Jorge,

> How I can execute monowall under bochs in Windows xp.

First of all... why would you want to run m0n0 in bochs?  You might
end up getting pretty strange results trying to do VLANing or captive
portal from within a virtualized environment.  m0n0's much better
suited on old hardware on a headless box with a CDROM and FLOPPY.

Quote from bochs documentation:
"Emulates an NE2000 compatible network card. On Windows NT/2000,
Linux, FreeBSD, and NetBSD, Bochs will forward packets to and from the
operating system so that the guest OS can talk on the physical
network. Unfortunately, on some platforms the guest OS can talk to any
machine on the network BUT NOT the host machine. On Windows and on
systems that allow the TAP or TUN/TAP interface, there is no such
limitation. Often the host machine may be configured so the guest OS
has access to the internet."

I'm not sure about everyone else, but I've had quite a bit of trouble
with NE2000 card and how it just doesn't seem to work in my m0n0 when
I tried.  So, you might run into some issues if this is the only card
that's provided by bochs.  If you search the list for stuff on NE2000,
here's a thread telling you about that and how NE2000 ISA doesn't
work:

http://m0n0.ch/wall/list/?action=show_msg&actionargs[]=77&actionargs[]=61


/sylikc