perhaps is also a route problem.

what do you receive if you type the command "route" in your linux box?

here my route list

[root@algol /etc]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.1.0 * 255.255.255.0 U 0 0 0 eth0
127.0.0.0 * 255.0.0.0 U 0 0 0 lo
default 192.168.1.1 0.0.0.0 UG 0 0 0 eth0

if one of these is missing you should add it (e.g. using "linuxconf" or the "route add" command)