Cannot ssh from FreeBSD to Linux

[P.V.N]

Hello all,

 I am running FreeBSD 5.1 and running Debian Woody stock 2.2.20 kernel.
My ISP is Comcast and each machine has an IP address assigned by DHCP,
from Comcast. 
My problem is: I am unable to ssh to the FreeBSD machine from my Debian
machine and cannot ssh to Debian from FreeBSD. However, I can ssh to
each machine from a Windows XP machine, also on Comcast. As a matter of
fact, all three of the machines are attached to the same hub. Also I can
ssh to both of the machines from the world, from work for instance.
Neither machine can ping each other and neither can hit port 80 on the
other machine. I access the machines via IP address so DNS is not an
issue, at least I don't think so.
Has anyone else experienced an issue like this? Does anyone know where I
may be able to get a resolution.

Thanks in advance,

PVN