ERROR: Can't Share File from a Computer connected via Shared Internet Connection

[i5c0r3]

I have 3 computers at home:
ComputerA and ComputerB are connected via an ADSL Modem with USB & RJ45 connectors.
ComputerC is connected to ComputerA's LAN Card.

PROBLEM: While using HFS on ComputerC, ComputerA can access but not ComputerB. Why? I've tried changing ports but no cigar.

MODEM:
Type: ADSL USB MODEM/ROUTER
IP: 192.168.1.1

ComputerA: I can see ComputerC's HFS
Type: Desktop
OS: Windows XP
USB IP: 192.168.1.2
RJ45 IP: 192.168.0.1 (Set by ICS to ComputerC)

ComputerB: I want to see ComputerC's HFS
Type: Desktop
OS: Windows 7
RJ45 IP: 192.168.1.3

ComputerC: Running HFS
Type: Laptop
OS: Windows 7
RJ45 IP: 192.168.0.2 (Set via ICS from ComputerA)

Please advice.
Thanks!

P.S.
Ping is ok in all three. Windows's File sharing even works, but not HFS.

[rejetto]

A is over 2 different networks
C is on a single network, that's different from the one of B.

possible solution is for A to bridge the 2 networks.
On Windows should be enough to select both networks, right click, "bridge".

Anyway, hfs itself can do nothing to help you, it's not a bug, it's a problem in your LAN.