How to access a Msft shared folder upstream through a firewall router?

I have succeeded in accessing a printer which is situated on an "inner IP
network," from an "outer IP network." I used an LPR technique, rather than
TCP/IP per se. The LPR technique was simpler. I established port
forwarding in the BEFSX41 router that delineates the inner net from the
outer net. BTW, the net addresses are different, between inner and outer
nets. Let's call them 192.168.1.0 for the outer, and 192.168.2.0 for the
inner, for the sake of this discussion. Subnet mask 255.255.255.0.

I can't seem to find the port numbers relevant to forwarding, for the
purpose of an XP computer in the outer net which must breach the firewall
and access a share on an Win2K Pro computer resident within the inner net.

I presume I'll have to enable some sort of tunneling protocol. The router
is a Linksys BEFSX41 and offers VPN. No wireless here; all hard wired.

Thanks for any tips.

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Sent via OE by John, from MERCURY